Sync polish round 3: conditional removes, settlement atomicity, mobile ribbon, large-vault responsiveness

[callumalpass]

Integrates round 3 of the overnight campaign. Every fix comes with a regression test that failed first.

Integration resolutions:

• ObsidianMirrorFileSystem.remove keeps reliability's expected-content fence and uses merge's cached entry lookup.

• The two independent quadratic-copy fixes in BinaryPartReader keep perf's version, which also releases the exhausted buffer. Both regression tests are kept.

• Duplicate Obsidian mock classes added by two agents are reduced to one set.

• Retire connections under the same lease that protects SDK mirror operations

• Coordinate mirror leases across renderer windows with Web Locks

• Prove tiny probe summaries see writes from other state adapters

• Bind hosted-deletion conflict resolution to the inspected local bytes

• Expose pending sync on the mobile ribbon when no status bar is available

• Pass inspected bytes through managed-file removal before trashing

• Reuse owned chunk tails instead of copying them for each upload part

• Rebase debounce and safety-net timestamps when the wall clock moves backwards

• Report unavailable diagnostics clipboard access without losing keyboard focus

• Read a tiny atomic checkpoint summary for background change probes

• Expose sync problems in workspace navigation when the status bar is unavailable

• Prove mobile late receipts, long freezes and suspended blob streams recover safely

• Enforce elapsed request deadlines when mobile timers resume late

• Keep the status bar paused when automatic sync is deliberately stopped

• Normalize sync migration markers and honor only boolean auto-sync choices

• Let an explicit pause suppress polling despite a previous offline problem

• Schedule sync and invalidate descendants for folder-only vault events

• Resolve proven physical path aliases without overwriting colliding files

• Avoid reserializing intact large history logs at startup

• Carry SDK binary preflight expectations into conditional materialization

• Treat a removed conflict copy source as a changed review, not a sync defect

• Bound portable glob matching instead of recursively exploding on wildcards

• Keep excluded scopes and file-issue actions readable in narrow sync panes

• Avoid quadratic attachment tail copies during mobile multipart uploads

• Reopen IndexedDB connections closed while mobile Obsidian was suspended

• Exercise restored destination state in the background badge focus test

• Name deletions in conflict choices and never copy an absent local version

• Restore the requested pane before scanning on workspace open

Validation:

• Clean npm ci: the multi-agent SDK patch applies.
• npm test: 383 pass, plus 10 lossless round trips.
• npm run lint and npm run check:mobile pass.