feat(registry): component_hash_id — stable id system for workflow references

Problem: canonical_id is readable but mutable; if a component is renamed,
all workflows referencing it by canonical_id break.

Solution: dual-id system
- component_hash_id: cmp_{sha256(canonical_id).slice(0,8)}, derived deterministically,
  never changes, safe for workflow references
- canonical_id: human-readable name, used for search and display
- idx:{canonical_id} KV key: reverse-lookup index for resolving canonical_id → hash_id

Changes:
- types.ts: SandboxResult.component_id → component_hash_id + canonical_id,
  added 'data' to category enum
- submitComponent.ts: deriveHashId(), writes idx: reverse-lookup on submit
- queryComponents.ts: full rewrite — removed KBDB dependency, uses SUBMISSIONS_KV;
  supports both cmp_* and canonical_id as query id; Phase 0 keyword search
  with note to upgrade to Vectorize in Phase 2
- sandboxAcceptance.ts: updated field names, fixed TextDecoder TS type
- ensureTemplate.ts: removed KBDB dependency, now a KV health check
- tests: updated component_id → canonical_id
- CONTRIBUTING.md: explain hash_id derivation and dual-id workflow reference syntax

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

registry/src/types.ts

@@ -7,8 +7,11 @@ import { z } from 'zod';
 export type Bindings = {
   WASM_BUCKET: R2Bucket;
   AI: Ai;
-  SUBMISSIONS_KV: KVNamespace;  // 零件元數據 + 可見性狀態（key = comp:{id}:{version}）
-  ANALYTICS_KV: KVNamespace;   // 執行統計匯總（key = stats:{id}:{version}）
+  // KV key 格式：
+  //   comp:{hash_id}:{version}   → 零件元數據（hash_id = cmp_ + sha256 前 8 碼）
+  //   idx:{canonical_id}         → canonical_id → hash_id 反查索引
+  SUBMISSIONS_KV: KVNamespace;
+  ANALYTICS_KV: KVNamespace;   // 執行統計匯總（key = stats:{hash_id}:{version}）
   ENVIRONMENT: string;
 };
 
@@ -28,9 +31,12 @@ export const GherkinTestSchema = z.object({
 });
 
 export const ComponentContractSchema = z.object({
+  // canonical_id：提交者填寫的可讀名稱（小寫底線），用於搜尋與 workflow 引用
+  // component_hash_id：由 Registry 在提交時派發，格式 cmp_{8碼hex}，workflow 引用此 id 才能保證永久不壞
+  // 兩者都可以在 workflow 中引用，Registry 會互相解析
   canonical_id: z.string().min(1).regex(/^[a-z][a-z0-9_]*$/, 'canonical_id 必須為小寫底線格式'),
   display_name: z.string().min(1),
-  category: z.enum(['logic', 'api', 'ui', 'style', 'anim']),
+  category: z.enum(['logic', 'api', 'ui', 'style', 'anim', 'data']),
   version: z.string().min(1).regex(/^v\d+$/, 'version 格式必須為 vN'),
   wasi_target: z.literal('preview1'),
   stability: z.enum(['floating', 'stable', 'pinned']),
@@ -64,7 +70,9 @@ export interface SandboxResult {
   failed_step?: SandboxStep;
   reason?: string;
   guide_anchor?: string;
-  component_id: string;
+  // 驗收通過後回傳兩個 id：
+  component_hash_id: string;  // cmp_{8碼hex}，workflow 引用用，永久不變
+  canonical_id: string;       // 可讀名稱，搜尋用
   version: string;
 }