Dissolve the by-kind @shared/config junk drawer per shared-layer governance: route each member by shape and actual consumer process — cross-process slices into types//utils//ai/, single-process code back into main/renderer (Invariant 1.1). Confirm each item's real consumer process rather than trusting the directional plan (API_SERVER_DEFAULTS is renderer-only, MIN_WINDOW_* is cross-process, providers.ts is renderer-only), and drop dead consts (ZOOM_LEVELS/ZOOM_OPTIONS, bookExts, thirdPartyApplicationExts).
Purge runtime logic from types/ so the bucket holds only declarations: move serializeError + AI-SDK error guards to utils/error.ts, the FileHandle factories/guards to utils/file/handle.ts, isSerializable + SerializableSchema to utils/serializable.ts, and the tab-instance guard/normalizer to utils/tabInstanceMetadata.ts. Tests follow the logic to utils/__tests__; the type-level ipc contract test is retired (its invariants kept as a breadcrumb for the future IpcApi Zod schema). types/ is now logic-free and test-free.
Also: remove the dead @shared mock from the packages/ui code-editor test so packages/ui no longer references production code; fix the data-classify preference generator prompts import and the update-languages output path to the relocated modules.
Update shared-layer-architecture (3.1 type/util test rule, 5/6 config dissolution) and renderer-architecture cross-references.
packages/shared was never a real pnpm workspace package (no package.json); it was referenced only through the @shared TypeScript path alias. Relocate it under src/ via git mv (143 files, detected as pure renames).
Repoint the @shared alias and include globs to src/shared across electron.vite.config.ts, tsconfig.{json,node,web}.json and vitest.config.ts; update scripts/check-custom-exts.ts, scripts/update-languages.ts, the eslint.config.mjs generated-file globs, the data-classify generator output targets, .github/CODEOWNERS path rules, and CLAUDE.md/docs/source-comment references.
The @shared alias name is unchanged, so all 1403 @shared/* import sites resolve without modification. Verified with typecheck:node, typecheck:web and the full test suite (700 files, 9739 tests passing).
