feat(mcp): introduce facade-v1 tool surface for Codex

[zzet]

Summary

• add a versioned, static 21-tool MCP facade backed by the existing 178 legacy handlers
• make facade-v1 the Codex default in hide mode, with capabilities for exact operation schemas and no deferred-tool promotion dependency
• preserve legacy client schemas and calls while preventing dedicated facade names from leaking into legacy sessions
• document the complete contract, effect model, migration table, rollout gates, and telemetry/privacy rules

Design and safety

• centralize facade-to-handler routing in one canonical operation registry
• keep read, local write, session write, control write, and external write boundaries homogeneous
• split effect-sensitive adapters: change.simulate fixes keep=false, overlay.simulate fixes keep=true, overlay.merge fixes to_disk=false, and edit.apply_overlay fixes to_disk=true
• keep temporal_verify out of read-only analyze and expose it through workspace_admin
• make direct deferred promotion session-aware so hidden legacy calls cannot mutate the global lazy registry
• refuse every effectful operation on remote federation routes
• make planning/workflow/preset recovery guidance reference tools callable on the active facade
• preserve freshness riders, overlay context, query logging, momentum safeguards, panic recovery, and hard gates across facade dispatch

Observability

• record consent-gated, allow-listed facade calls, bounded outcomes, validation failures, status, and coarse latency buckets
• collapse unknown caller-provided operation/domain values to fixed sentinels; no path, symbol, query, or raw operation is recorded
• attach _meta.gortex_facade routing metadata and log surface/facade/operation/canonical-tool fields locally

Validation

• canonical registry covers 178/178 legacy MCP tools
• Codex first tools/list is exactly 21 static facade names and stays below the 15 KB regression ceiling
• real protocol test covers uncompressed read(operation="file") plus guarded edit(operation="file", dry_run=true) without a disk write
• all tracked Go packages pass
• go vet ./internal/mcp ./internal/daemon ./internal/telemetry ./cmd/gortex
• git diff --check

Related to #241: this removes the Codex deferred-read mismatch and unavailable-tool guidance failure mode. Hook classifier and daemon-transport behavior remain independently testable concerns.