chore: remove dead code (59 unused files + ~125 unused exports) (#1835)

* chore: remove dead/unreferenced files across ui, vscode

Remove 59 unused source files (components, hooks, lib utils, stores,
barrels, and orphaned vscode github modules) that are not imported by
any entry-reachable code. Also drop a stale test mock for the removed
execCommands module.

Co-authored-by: Serhii Dziupin <makeittech@users.noreply.github.com>

* refactor: remove unused exported symbols (types, functions, consts, hooks)

Remove exported symbols whose identifier is referenced nowhere in the
repository (verified via repo-wide search), across ui types/contracts,
lib utilities, sync layer, stores, and components. Also drop the few
imports/private helpers orphaned by these removals.

Co-authored-by: Serhii Dziupin <makeittech@users.noreply.github.com>

* refactor: remove more unused exports (desktop, shortcuts, worktree, vscode)

Continue removing repo-wide unreferenced exported functions, consts and
types across lib/desktop, shortcuts, worktreeSessionCreator, sync, and
vscode gitService, with cascading orphaned helpers/imports cleaned up.

Co-authored-by: Serhii Dziupin <makeittech@users.noreply.github.com>

* chore: add dead-code cleanup tooling

* refactor: checkpoint dead-code cleanup

* refactor: remove dead-code suppressions

---------

Co-authored-by: Serhii Dziupin <makeittech@users.noreply.github.com>
Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>

packages/ui/src/components/views/git/gitGraph.ts

@@ -1,6 +1,6 @@
 import type { GitLogEntry } from '@/lib/api/types';
 
-export type LaneColor = string;
+type LaneColor = string;
 
 /**
  * Describes one visible line/curve in a commit row's SVG.
@@ -14,7 +14,7 @@ export type LaneColor = string;
  *  - 'branch-out' : bezier from (dot-x, dot-y) to (toLane-x, 100%) — new parent lane opens
  *  - 'merge-in'   : bezier from (fromLane-x, 0) to (dot-x, dot-y) — lane converges here
  */
-export interface ConnectorSegment {
+interface ConnectorSegment {
   fromLane: number;
   toLane: number;
   color: LaneColor;
@@ -40,7 +40,7 @@ const LANE_COLORS: LaneColor[] = [
   'var(--status-info)',
 ];
 
-export function laneColor(lane: number): LaneColor {
+function laneColor(lane: number): LaneColor {
   return LANE_COLORS[lane % LANE_COLORS.length];
 }