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/factory.ts

@@ -1,16 +1,11 @@
-import type { HostConfig } from '../scripts/host-config';
+import { defineHost } from './define-host';
 
-const factory: HostConfig = {
+const factory = defineHost({
   name: 'factory',
   displayName: 'Factory Droid',
   cliCommand: 'droid',
   cliAliases: ['droid'],
 
-  globalRoot: '.factory/skills/gstack',
-  localSkillRoot: '.factory/skills/gstack',
-  hostSubdir: '.factory',
-  usesEnvVars: true,
-
   frontmatter: {
     mode: 'allowlist',
     keepFields: ['name', 'description', 'user-invocable'],
@@ -23,11 +18,9 @@ const factory: HostConfig = {
     ],
   },
 
-  generation: {
-    generateMetadata: false,
-    skipSkills: ['codex'],  // Codex skill is a Claude wrapper around codex exec
-  },
-
+  // Non-mechanical rewrites: the global path becomes $GSTACK_ROOT (resolved by
+  // the preamble env vars), plus an extra review-path rewrite the derived trio
+  // doesn't cover.
   pathRewrites: [
     { from: '~/.claude/skills/gstack', to: '$GSTACK_ROOT' },
     { from: '.claude/skills/gstack', to: '.factory/skills/gstack' },
@@ -43,22 +36,8 @@ const factory: HostConfig = {
     'use the Glob tool': 'find files matching',
   },
 
-  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: false,
-    linkingStrategy: 'symlink-generated',
-  },
-
   coAuthorTrailer: 'Co-Authored-By: Factory Droid <droid@users.noreply.github.com>',
   learningsMode: 'full',
-};
+});
 
 export default factory;