refactor(mobile): add a robust @/ import alias for apps/mobile/src

[juliusmarminge]

The problem

Audit #8: mobile has 101 imports at ../../../ depth and 15 at ../../../../, while web resolves ~/* against its src (814 uses). Mobile had no tsconfig paths, so every deep import is edit friction and every file move silently breaks relative paths across the app.

The fix

• apps/mobile/tsconfig.json — "paths": { "@/*": ["./src/*"] }, matching the web ~/* precedent. Expo 57's Metro already resolves tsconfig paths natively (exp.experiments.tsconfigPaths defaults to true in @expo/cli's instantiateMetro), so no Metro config change is needed — and Expo's resolver is importer-scoped (it skips requests originating in node_modules), which a plain prefix hook is not.
• vite.config.ts (root) — mobile unit tests run under the root vitest config, which has no knowledge of tsconfig paths, so the mapping is mirrored there as a @/ → apps/mobile/src/ alias. The existing web ~ alias is kept byte-for-byte via the array form.

Migrated a bounded, representative set of deep imports rather than all ~200 files, mixing runtime values, type-only imports, .ts and .tsx, across four features (sharing, connection, threads, settings). The rest can migrate incrementally — both styles coexist.

Verification (no UI change → no screenshots)

• Real bundles, both platforms (expo export --dev, apps/mobile): iOS Bundled apps/mobile/index.ts (3886 modules) and Android Bundled apps/mobile/index.ts (4041 modules) — the full app graph, including the migrated @/ imports, resolves through Expo's tsconfig-paths resolver with no Metro override.
• TypeScript: tsc --noEmit in apps/mobile — clean with the migrated @/ imports.
• Vitest (runtime resolution through the root alias): incoming-share-model, incoming-share-inbox, environmentSections, new-task-project-selection — 4 files / 57 tests passed, all resolving @/lib/... value imports at runtime. Web alias regression: browserDefaults.test.ts (~ imports) passes unchanged.

Revisions

Initial head 2efab1e also added a custom config.resolver.resolveRequest hook in metro.config.js. Audit review (and a re-run of both platform exports) confirmed Expo's built-in tsconfig-paths resolution makes the hook redundant, and that it would additionally hijack a dependency's own @/… imports from node_modules, which Expo's importer-scoped resolver correctly leaves alone. 84cc687 removes it; metro.config.js is back to unchanged.

_{Model: callstack/Apex; harness: Apex in T3 Code (pi).}

Summary by CodeRabbit

• Chores
  • Standardized mobile app import paths with a shared alias, including support in the test tooling.

[macroscopeapp]

Approvability

Verdict: Approved at 84cc687

Macroscope's review found this PR approvable — This is a bounded import-path refactor with matching TypeScript and test-tool configuration; all migrated imports continue to target the same existing modules. It does not add user-facing behavior, alter product defaults, or suppress static-analysis diagnostics.

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ℹ️ Recent review info

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Reviewing files that changed from the base of the PR and between 2efab1e and 84cc687.

📒 Files selected for processing (1)

• vite.config.ts

🚧 Files skipped from review as they are similar to previous changes (1)

• vite.config.ts

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📝 Walkthrough

Walkthrough

TypeScript and Vite now resolve the mobile @/ alias. Selected imports in connection, settings, sharing, and thread code use that alias.

Changes

Mobile import aliases

Layer / File(s)	Summary
Configure mobile alias resolution apps/mobile/tsconfig.json, vite.config.ts	TypeScript maps @/* to ./src/*. Vite retains the ~ mapping and adds a mapping for @/ to the mobile source directory.
Use aliases in mobile imports apps/mobile/src/features/connection/*, apps/mobile/src/features/settings/components/SettingsRow.tsx, apps/mobile/src/features/sharing/*, apps/mobile/src/features/threads/new-task-project-selection.ts	Selected imports use @/ paths instead of relative paths.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~8 minutes

Change: Refactor

Merge Risk: ⚪ Minimal · up to 84cc6

The mobile alias configuration consistently targets the mobile source directory, so the selected migrated imports are ready to merge.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 2 functions across 8 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly and concisely describes the main change: adding a robust @/ import alias for the mobile source directory.
Description check	✅ Passed	The description clearly explains the problem, the implementation, the migration scope, and verification results. It does not use the template headings or include the checklist, but it provides the req…

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Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	13.5 KiB	13.5 KiB	+16 B (+0.1%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.0 KiB	7.1 KiB	+10 B (+0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.5 KiB	6.5 KiB	+6 B (+0.1%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	56.3 KiB	56.3 KiB	0 B (0.0%)	66.4 KiB	✅
Codex	Live turn messages	10	10	0 (0.0%)	21	✅
Claude	Total thread wire	13.5 KiB	13.5 KiB	−11 B (−0.1%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.1 KiB	7.1 KiB	−7 B (−0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.4 KiB	6.4 KiB	−4 B (−0.1%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	57.0 KiB	57.0 KiB	0 B (0.0%)	66.4 KiB	✅
Claude	Live turn messages	9	9	0 (0.0%)	21	✅

Baseline: d7819c1 · PR result: 84cc687 · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

• Codex decoded thread snapshot: 113.9 KiB
• Claude decoded thread snapshot: 114.6 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

Dismissing prior approval to re-evaluate 84cc687