refactor: mutation-default approval, tab-manager actions, DO tracking, CLA

[braden-w]

Removes the per-action destructive flag and makes all mutations require approval by default. The toolTrust table (CRDT-synced [Always Allow]) already solves approval fatigue—this change flips the default so developer omission can't silently bypass approval.

The old system required destructive: true on each action. Out of 8 tab-manager mutations, only tabs.close had it—the other 7 auto-executed with zero friction. That's not a deliberate choice; it's an omission.

// BEFORE: developer must remember to opt in
close: defineMutation({
  destructive: true,  // ← forget this and mutations auto-execute
  handler: () => { ... },
}),

// AFTER: approval is automatic for all mutations
close: defineMutation({
  handler: () => { ... },  // needsApproval: true by action type
}),

BEFORE                                  AFTER
─────                                   ─────
actionsToClientTools()                  actionsToClientTools()
  for each action:                        for each action:
    if action.destructive                   if action.type === 'mutation'
      → needsApproval: true                   → needsApproval: true
    else                                    if action.type === 'query'
      → (omitted, auto-executes)              → (omitted, auto-executes)

Result:                                 Result:
  tabs.close  → approval ✓               tabs.close    → approval ✓
  tabs.open   → auto-execute ✗           tabs.open     → approval ✓
  tabs.pin    → auto-execute ✗           tabs.pin      → approval ✓
  tabs.save   → auto-execute ✗           tabs.save     → approval ✓
  tabs.dedup  → auto-execute ✗           tabs.dedup    → approval ✓
  tabs.search → auto-execute ✓           tabs.search   → auto-execute ✓

The trust escalation flow is unchanged—users click [Always Allow] once per mutation and the preference syncs across devices via CRDT.

Other changes in this branch

Tab manager: Extract shared tab helpers (findDuplicateGroups, groupByDomain) from quick-actions into tab-helpers.ts and expose tabs.dedup and tabs.groupByDomain as workspace actions. Add trust revocation settings popover in the AI drawer so users can manage their [Always Allow] grants.

API: Track Durable Object instances with storage size on every access (durable_object_instance table + migration). Add deleteStorage RPC method to BaseSyncRoom. Simplify afterResponse queue drain API.

Infrastructure: Add CLA for commercial licensing. Redesign GitHub issue templates and PR template for prose-first contributions. Add CODEOWNERS.

Docs: Writing voice financial language guideline. Git skill compression (remove redundant sections, collapse ASCII art catalog). Piggybacking storage tracking article. Multiple specs marked as implemented.