docs: correct all owned docs against the shipped mirror-shell app

[kevinthelago]

Summary

Every doc in this stream's lane (CLAUDE.md, README.md, .github/PROJECT_PLAN.md, and the
four docs/*.md protocol/handoff docs) described an earlier version of the app — a standalone
git-editing IDE with a 5-tab Files/Find/Edit/Git/Run shell — that no longer exists. It was
superseded by the read-only mirror-shell redesign, and none of the docs, including CLAUDE.md's
own folder structure and data-flow sections, matched a real code path anymore.

• CLAUDE.md — reconciled against the app's current state (folder structure, data flows,
  orphaned-code table). This also fixes residual drift in the prior refresh (CLAUDE.md is stale: documents a shell, a workflow, and a tech-debt list that no longer exist #260): the
  fleet//screens/ files it still listed were already deleted (24 source files are unreachable from any route — triage and clear the orphans #262), and the Planner tab's
  live/blueprints segment strip was removed (App Store submission: standalone demo mode for review completeness (2.1) #250), orphaning LivePlanBoard /
  BlueprintsSection / plannerBoard.ts.
• docs/tunnel-live-planning.md — documents that the dedicated live-plan protocol (both read
  and write sides) is now fully orphaned; the desktop's live planning session is reached today
  via plain session chat (findPlannerPane + SessionChat), not a structured stepper view.
• docs/redesign-migration-plan.md — replaced the fully-shipped M1–M9 standalone-IDE plan
  (condensed as history) with the current in-flight redesign: umbrella Umbrella: reprioritised shell — Glance · Planner · Studio · Skills · Automations #233 (shell
  reprioritisation) and Umbrella: resync store_state payloads with base-studio-code develop (contract v2 drift) #234 (store_state payload-contract drift), with live per-domain status
  pulled from the issue tracker.
• docs/git-feature-handoff.md — rewritten from a "finish this" TODO for a Git tab that no
  longer exists into a reference for the current git/GitHub layer: the file push/pull path is
  complete but UI-orphaned; the Planner's GitHub-publish path is the one live consumer today.
• docs/kit-bindings.md — created, then replaced with a verified version of the
  already-existing (but previously unlinked-from-here) designer-spec wiring contract for the
  data-driven kit system, after confirming my first-pass guess (a components/themes
  mirror-domain contract) targeted the wrong feature entirely.
• docs/planner-sync-protocol.md — light-touch update; the wire contract was already accurate,
  added the app-level wiring (PlannerSyncContext, the sync conflict editor) it never described.
• .github/PROJECT_PLAN.md — corrected mobile's architecture/stack/test-gate description
  (pre-tunnel-server, pre-mirror-redesign stale); left the shared roadmap/version tables
  untouched as a planner-owned call.
• README.md — fixed repo casing in badge/issue links, the actual branch-naming convention
  ({number}-slug, not issue-{number}/slug), a non-existent workflow filename, and a tagline
  still describing the old standalone-IDE framing.

Note on base branch

This repo's remote has no develop branch — every prior merge in its history went straight into
main (confirmed via gh api repos/.../branches), so this PR targets main to match that.
Retarget if a develop branch exists elsewhere I'm not seeing.

Test plan

• git diff --stat confirms only the 7 owned doc files changed (0 .ts/.tsx/.json
  touched) — tsc --noEmit / npm test outcomes are unaffected by construction.
• Every factual claim (file paths, orphan status, wire message shapes, primitive lists) was
  verified against the actual current source (origin/main), not assumed from memory.
• Director review

Co-Authored-By: Claude Sonnet 5 noreply@anthropic.com