[Kanak234]

The first-launch editor was only 127 px wide at 1366×768. This replaces the competing right docks with a 48 px activity bar, collapsible sidebar and bottom panel; the editor region is now 1044 px at that resolution (1598 px at 1920×1080). Literal ampersands render correctly in tool and file tabs.

Implemented Track A: saved splitter sizes and Ctrl+B/Ctrl+J, command centre and palette, incremental Quick Open and workspace search, Git view, VS Code menu order, shared Medhā Dark/Light themes, minimap, Welcome/Recent/examples, and real document/Git/compiler status with optional system monitoring. Original menu actions remain reachable and are regression-tested.

Required-check prerequisites B4/B6/B7 are separate commits. UI testing also found B8 (callbacks after process teardown) and B9 (discarding unsaved documents); both are documented and fixed. All commits use the prescribed author.

Validation on Linux with PySide6 6.12:

• Offline pytest: 106 passed, 1 explicitly skipped network test.
• python -m pyflakes medha: clean.
• Offscreen UI smoke: 20 passed, including every menu action from Welcome with cancelled dialogs/stubbed external builds, actual viewport width in both resolutions/themes, settings restoration, keyboard toggles, navigation and close-cancellation checks.
• Real 1366×768 and 1920×1080 screenshots: before/after gallery. Intermediate captures are included.
• Step-by-step verification notes.

Review limits: the original app had no light theme, so before-light captures are unavailable. B3/PTTY-ConPTY and B5 remain Track B work; the existing terminal job-control warning is visible in the unedited screenshots. Windows/manual release acceptance remains pending. No Store release or merge is included.