refactor(hosts): defineHost() factory — 10 copy-paste host files become declarations

hosts/*.ts were ten copies of one file: runtimeRoot byte-identical in 9/10,
pathRewrites mechanically derivable from the host name for 7/10, the 11-entry
toolRewrites map byte-identical between openclaw and gbrain, and every asset
change a 10-file edit (cursor and slate had already fallen out of three other
hand-maintained lists). defineHost() owns the defaults; each host file now
declares only what makes it different (slate/cursor: 8 lines each). Shared
constants: CROSS_MODEL_RESOLVERS, GBRAIN_RESOLVERS, EXEC_STYLE_TOOL_REWRITES.
Genuinely-different things stayed explicit: codex/factory $GSTACK_ROOT
rewrites, hermes's tool vocabulary, claude's denylist+prefixable install,
opencode's wider runtimeRoot.

Proof: JSON.stringify(ALL_HOST_CONFIGS) dump-diff before/after EMPTY (and a
runtime walk confirmed no function-valued or undefined-keyed fields, so the
JSON diff is complete); gen:skill-docs --host all zero-diff; host-config +
gen-skill-docs + idempotency suites 485/485. Host files 595 -> 285 lines.
docs/ADDING_A_HOST.md teaches the factory pattern.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

hosts/claude.ts

@@ -1,15 +1,10 @@
-import type { HostConfig } from '../scripts/host-config';
+import { defineHost } from './define-host';
 
-const claude: HostConfig = {
+const claude = defineHost({
   name: 'claude',
   displayName: 'Claude Code',
-  cliCommand: 'claude',
-  cliAliases: [],
 
-  globalRoot: '.claude/skills/gstack',
-  localSkillRoot: '.claude/skills/gstack',
-  hostSubdir: '.claude',
-  usesEnvVars: false,
+  usesEnvVars: false,  // primary host — literal ~ paths, no $GSTACK_ROOT env vars
 
   frontmatter: {
     mode: 'denylist',
@@ -24,14 +19,6 @@ const claude: HostConfig = {
 
   pathRewrites: [],  // Claude is the primary host — no rewrites needed
   toolRewrites: {},
-  suppressedResolvers: ['GBRAIN_CONTEXT_LOAD', 'GBRAIN_SAVE_RESULTS'],
-
-  runtimeRoot: {
-    globalSymlinks: ['bin', 'browse/dist', 'browse/bin', 'gstack-upgrade', 'ETHOS.md'],
-    globalFiles: {
-      'review': ['checklist.md', 'TODOS-format.md'],
-    },
-  },
 
   install: {
     prefixable: true,
@@ -40,6 +27,6 @@ const claude: HostConfig = {
 
   coAuthorTrailer: 'Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>',
   learningsMode: 'full',
-};
+});
 
 export default claude;