feat: show current-line git blame by default

docs/architecture.md

@@ -11,6 +11,7 @@ One editor crate; the workspace also includes its patched Crossterm dependency.
 - `editor`: owns shared buffer lifecycle/text/saved state/undo history and independent tab/pane layouts, focused views, modes, selections, searches, explorers, and comparisons; session-wide clipboard policy, independent registers and owned-system fragment metadata, semantic native repeat, action metadata, command-palette and file-picker focus/dispatch, key notation, key-sequence/count prefixes and binding resolution, modal paste policy, saving, command ownership, capabilities, and validated edit effects. Its low-level interface returns an `Invocation` when an external command is selected.
 - `chrome`: owns validated top/bottom bar anchor groups, segment title templates and padding/edge options, builtin defaults, named-value validation, and typed command/search popup anchors. Both bars accept the same segments and layout options. It has no terminal geometry or render callbacks.
 - `battery`: reads native charge off the input thread, sampling immediately and every 30 seconds through an interruptible worker. macOS CoreFoundation references are type-checked and owned Copy/Create values released; Linux reads system battery sysfs and Windows reads native power status. A one-slot atomic mailbox retains the latest sample; absent/invalid readings clear cached presentation instead of inventing a percentage. Session starts collection only while an unoverridden battery segment is configured.
+- `blame`: owns local current-line Git attribution against the supplied in-memory text and a cancellable background worker. Git-backed jj uses its working-copy parent's commit through an isolated temporary Git store; active refs/checkouts remain untouched.
 - `files`: owns the gitignore-aware directory/file catalog, authoritative OS paths, compact tree projection, query filtering, browse/search focus, expansion/selection restoration, navigation, and scan/error state shared by floating and docked presentations.
   Virtual file leaves retain their original catalog input index for caller-owned annotations; scanned entries and directories remain unannotated.
 - `diff`: owns searchable Before/After selection, category, focus and explorer visibility, request freshness, read-only comparison DTOs, aligned rows with cached grapheme-level change ranges, and shared vertical/independent horizontal offsets. Changed paths form a virtual `files::FilePicker` catalog, reusing the normal tree projection, filtering, and navigation without scanning disk. It has no subprocess or terminal dependencies.
@@ -50,6 +51,8 @@ Frontends borrow `top_bar_config()` and `bottom_bar_config()` for validated orde
 Frontends borrow `popup_config()` for independently configured command/search anchors. The TUI resolves each anchor against the chrome-free workspace using the existing bounded popup size; startup configuration does not alter buffer text, modal input, or notification positioning.
 Frontends borrow `lsp_label()` / `lsp_names()` for the focused buffer's cached ready-server metadata. Initialization-only worker events trigger status redraws independently of diagnostics; session synchronization clears or replaces names when focus changes or a server retires. `notification_visible()` gates persistent operation/diagnostic popups independently of stored message text, so Escape dismissal neither alters text nor collapses carets. Display-only home abbreviation does not change document identity.
 
+Current-line blame is enabled by default. Session schedules one request per focused tab/pane/buffer/text-revision/path/row identity and rejects superseded results, including results returning after navigation away and back. The editor stores a sanitized borrowed label; rendering uses only spare cells after the current logical line's final visible continuation and hides it when the primary caret is offscreen. Disabling drops the worker; comparisons and immutable buffers never schedule live blame.
+
 Frontends inspect `file_picker()` for query, presentation, view, explorer-local INSERT/filter subfocus, selection, and errors, and iterate borrowed `FileRow` metadata (actual path, display label, directory flag, visible depth, expansion). Dock side is a logical preference. They allocate rectangles, add folder suffixes/colors, and render; hierarchy, filtering, parent/child navigation, focus transitions, and selected-file opening remain backend-owned.
 Frontends inspect `diagnostics()` and `diagnostic_at_cursor()` for validated active-buffer annotations. Diagnostics are owned by core LSP or a plugin and buffer revision; text changes clear them. Native server retirement removes only that server's contribution, preserving sibling diagnostics. The TUI underlines annotated text, colors affected gutter numbers by severity, and displays the primary caret's diagnostic message without replacing search/selection backgrounds.
 Frontends borrow `semantic_tokens()` for sorted, single-line grapheme spans from the active buffer. Immutable `Arc` slices are shared by native LSP and buffer storage; painting does not copy tokens. Text/path changes discard overlays, and native updates validate the whole applicable annotation batch before mutation. The TUI merges semantic styling into its existing glyph pass above syntax foregrounds but below diagnostic/search/selection/caret styling.

docs/configuration.md

@@ -13,6 +13,7 @@ Rejected configuration opens a centered floating **Configuration error** window,
 Vamp.configure do |config|
   config.leader = "space"
   config.clipboard_mode = "system"
+  config.git_blame = true # false disables current-line attribution
   config.file_explorer_side = "right"
   config.file_explorer_view = "tree"
   config.file_picker_view = "tree"
@@ -44,6 +45,8 @@ Plugin paths resolve relative to the config file, not the shell's working direct
 `config.file_explorer_side` defaults to `"right"`; other choices are `"left"`, `"top"`, and `"bottom"`. Independent `file_explorer_view` / `file_picker_view` preferences both default to `"tree"` and accept `"list"` as an alternative. Invalid preference strings report notices and retain defaults while valid bindings still install. Non-string/empty values disable the whole configuration like other Ruby type errors.
 `config.clipboard_mode` accepts `"system"` (default) or `"separate"`. An invalid policy string reports a notice and retains System while valid bindings still install; non-string/empty values reject the whole Ruby configuration.
 
+`config.git_blame` defaults to `true`; set it to `false` to disable current-line inline Git blame and its background worker. Only literal Ruby booleans are accepted; other values reject the configuration. Toggle it for the running session with `:git_blame.toggle`, its palette action, or a custom binding such as `config.bind "leader b", config.core.git_blame.toggle`. There is no default shortcut.
+
 `config.diff_context_lines = 10` sets how many unchanged aligned lines appear above and below each diff change; it defaults to `10` and accepts nonnegative integers, including `0` for changes only. `config.diff_expand_lines = 15` sets how many additional lines each directional expansion reveals per keypress; it defaults to `15` and accepts positive integers. Both are bounded by the platform's Rust `usize` maximum (`18446744073709551615` on 64-bit systems). Floats, strings, booleans, negative or oversized values, and a zero expansion step reject the whole Ruby configuration.
 
 `config.diff_view_mode` selects the initial view for each new comparison: `"split"` (default) or `"unified"`. `config.diff_split_orientation` selects `"vertical"` (left/right, default) or `"horizontal"` (above/below) for split views. Invalid values reject the configuration. Normal-mode **Space v** cycles split/unified; **Space s** flips split orientation. These controls affect the current comparison, not startup defaults, and retain their choices across file switches and tabs. Orientation changes apply only in split view.
@@ -169,6 +172,7 @@ Normal `C` / `D` / `Y` change/delete/copy the cursor-to-line-end suffix through
 | Normal | `diff`, `diff.mode.toggle`, `diff.view.toggle`, `diff.orientation.toggle` |
 | Normal, Insert, Visual, Command, Search | `diff.close` |
 | Normal, Insert, Visual, Command, Search | `word_wrap.toggle` |
+| Normal, Insert, Visual, Command, Search | `git_blame.toggle` |
 | Normal | `pane.split_horizontal`, `pane.split_vertical`, `pane.focus_left`, `pane.focus_down`, `pane.focus_up`, `pane.focus_right`, `pane.close`, `pane.force_close` |
 | Normal | `tab.new`, `tab.previous`, `tab.next`, `tab.close`, `tab.force_close` |
 | Normal | `jump_back`, `jump_forward` |

docs/editing.md

@@ -206,6 +206,14 @@ Toggling preserves the source caret and anchors a visible caret to its previous
 
 Text wraps at word boundaries where possible, with grapheme-safe breaks for long words. Whitespace is preserved; tabs keep their source-column stops and wide/combining Unicode characters retain their geometry. Only the first display segment shows a line number. Syntax and semantic colors, diagnostics, search matches, selections, and cursors follow the wrapped text. Motions and counts still use source lines, so `j`/`k`, Home/End, and saved file contents are unchanged. Vertical wheel input scrolls continuation rows; switching wrapping off restores horizontal scrolling.
 
+## Current-line Git blame
+
+Inline blame is enabled by default in ordinary live file buffers. The primary caret's line shows its author, commit summary, and short commit ID after the document text; changed or newly inserted tracked-file lines show **Uncommitted**, including unsaved edits. Git-backed jj repositories use the working-copy revision's single parent, not a potentially stale Git HEAD. Merge working copies with multiple parents omit attribution.
+
+Loading happens in the background without network access or changing repository refs/checkouts. Missing, untracked, unborn, and non-repository files have no indicator; immutable historical buffers and comparison views do not receive live-file attribution. Moving, editing, switching views, or disabling clears stale results. The indicator is hidden when the caret is offscreen or the full label cannot fit; wrapped lines use their final visible continuation without covering text, selections, or the caret. Popups retain their normal layering.
+
+Use `:git_blame.toggle`, the palette action, or remappable `config.core.git_blame.toggle`; there is no default keybinding. Set `config.git_blame = false` to disable it at startup. Disabling stops the worker and clears the label without changing text or undo history.
+
 ## Panes and splits
 
 Splits can be nested in either direction. The new pane receives focus. Panes showing the same buffer share text, saved state, diagnostics, and undo/redo history, but retain independent carets, selections, modes, searches, and vertical/horizontal viewports. Buffer navigation changes only the focused pane. A file is still loaded once, even when displayed in several panes.