Part of #9598, on top of #10258. Addresses the review comment there about the dev API.

After #10258 the dev engine watches tsconfig files, but being watched is not enough: a tsconfig is neither a module nor a transform dependency, so the HMR mapper observes the change and maps it to `Noop`, and dev output keeps the old transform and resolution results. A tsconfig edit affects every module the tsconfig governs, which neither an HMR patch nor a partial scan can represent, so the only correct reaction is a full rebuild with fresh caches.

Discovered tsconfig paths are remembered in a set on `RawTransformOptions` that `discover_tsconfig_file` fills during watch registration. The set deliberately survives `clear_cache`, so the bundling task can still classify a changed path after the caches were dropped. When a changed file hits the set, the bundling task clears the resolver and tsconfig caches and upgrades itself to `TaskInput::FullBuild`.

Registering the tsconfig as a transform dependency was considered and rejected: the HMR mapper would patch every module the tsconfig governs instead of doing one clean rebuild, and a pure `Hmr` task never clears the caches, so those patches would still use the stale options.

Review notes: detection lives in `BundlingTask`, not the coordinator, because the coordinator must not lock the bundler while a running build holds the lock. The upgrade happens after the `watchChange` hooks so they still see the changed files. The coordinator reads `requires_full_rebuild()` only at scheduling time, so a task that upgrades itself mid-run completes through the normal `InProgress` path.

Client notification (a `FullReload` update so browsers refresh automatically) and the dev fixtures come in a follow-up.

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## [1.2.0] - 2026-07-15

### 🚀 Features

- dev: skip shipping factories for newly imported top-level modules (#10223) by @h-a-n-a
- dev: per-client ship map for HMR patch sizing (#10208) by @h-a-n-a
- dev: client-side HMR (#10164) by @h-a-n-a
- dev: send a full-reload update to clients when a tsconfig changes (#10262) by @shulaoda
- treat `import.meta['url']` and `import.meta['ROLLUP_FILE_URL_*']` as side-effect free (#10267) by @sapphi-red
- rewrite `import.meta['url']` (#10251) by @sapphi-red
- add `FILE_NOT_FOUND` error (#10220) by @sapphi-red
- treat `import.meta.ROLLUP_FILE_URL_*` as side-effect free (#10217) by @sapphi-red

### 🐛 Bug Fixes

- sourcemap: preserve unmapped boundaries during composition (#10254) by @hyfdev
- `[format]` in `*FileNames` option for ESM format should be `es` instead of `esm` (#10214) by @sapphi-red
- sourcemap: preserve coarse mappings during composition (#10249) by @hyfdev
- rolldown_plugin_vite_import_glob: support tsconfig paths with `import.meta.glob` (#10167) by @sapphi-red
- dev: clear tsconfig caches for bare full builds (#10276) by @shulaoda
- dev: force a full rebuild when a tsconfig changes (#10261) by @shulaoda
- treat rooted drive-less module ids as absolute in preserveModules naming (#10235) by @IWANABETHATGUY
- watch: rebuild when tsconfig files change (#10258) by @shulaoda
- watch: drop tsconfig-merged transform options on each rebuild (#10257) by @shulaoda
- incorrect `EMPTY_IMPORT_META` warning for `import.meta.ROLLUP_FILE_URL_*` for CJS output (#10221) by @sapphi-red
- deconflict: rename CJS locals shadowing wrapped-ESM namespace objects (#9970) by @IWANABETHATGUY
- rolldown: drop the unused runtime module after entry-level external flattening (#10237) by @IWANABETHATGUY
- rolldown: re-propagate has_dynamic_exports to transitive star importers (#10239) by @IWANABETHATGUY
- tree-shaking: tree-shake destructured dynamic import namespace bindings (#10213) by @logaretm
- s390x: use json-escape-simd 3.1.1 for big-endian JSON escaping fix (#10211) by @satyamg1620

### 🚜 Refactor

- dev: move full-reload to client side (#10207) by @h-a-n-a
- readability follow-ups to the ReplaceWith migration (#10286) by @IWANABETHATGUY
- replace take_in-then-write-back with ReplaceWith and by-value moves (#10285) by @Boshen
- share the main resolver's cache with the transformer's tsconfig lookups (#10205) by @shulaoda
- rolldown: extract the ns star-external __reExport emission rule into LinkingMetadata (#10238) by @IWANABETHATGUY
- rolldown: unify link/generate diagnostics into a Diagnostics accumulator (#10234) by @IWANABETHATGUY
- sourcemap_filenames: drop dead sourcemap-filename plumbing (#10189) by @IWANABETHATGUY
- extract external import symbol merging into a method (#10224) by @IWANABETHATGUY
- rolldown: skip CJS namespace merging under strict execution order (#10203) by @hyfdev
- resolve the manual tsconfig per file instead of once at startup (#10200) by @shulaoda
- rolldown: route interop ESM init emission through a shared init-target view (#10202) by @hyfdev
- rolldown: collapse vestigial wrap-kind state and share chunk sort helper (#10201) by @hyfdev

### 📚 Documentation

- show plugin kinds in JSDoc and each hook's description (#10218) by @sapphi-red
- add an explanation about removing imports from external modules without any messages (#10215) by @sapphi-red

### ⚡ Performance

- sourcemap: owned merge in SourceJoiner::join (4005->5 allocs/chunk) (#10250) by @Boshen
- avoid redundant sourcemap string copies in collapse and minify paths (#10093) by @Boshen

### 🧪 Testing

- code-splitting: establish strict-order review baselines (#10287) by @hyfdev
- dev: add hot API test cases (#10181) by @h-a-n-a
- code-splitting: normalize strict execution order variants (#10277) by @hyfdev
- code-splitting: harden strict execution order coverage (#10252) by @hyfdev
- code-splitting: add strict execution order regressions (#10253) by @hyfdev

### ⚙️ Miscellaneous Tasks

- deps: update github actions (#10241) by @renovate[bot]
- deps: update oxc to 0.140.0 (#10274) by @shulaoda
- update Yunfei's GitHub username (#10275) by @hyfdev
- deps: update napi (#10260) by @renovate[bot]
- deps: update test262 submodule for tests (#10266) by @rolldown-guard[bot]
- deps: update dependency vite-plus to v0.2.4 (#10256) by @renovate[bot]
- deps: update napi (#10240) by @renovate[bot]
- deps: update oxc resolver to v11.24.2 (#10245) by @renovate[bot]
- deps: update rust crates (#10244) by @renovate[bot]
- disable Renovate updates for idna_adapter (#10248) by @shulaoda
- deps: update oxc resolver to v11.24.1 (#10232) by @renovate[bot]
- deps: update rust crate oxc_sourcemap to v8.1.1 (#10233) by @renovate[bot]
- deps: update dependency rolldown-plugin-dts to ^0.27.0 (#10206) by @renovate[bot]
- deps: upgrade sugar_path to v3 (#10230) by @hyfdev
- add `dist-*` to `.gitignore` in sourcemap-filenames/hash-final-content fixture (#10216) by @sapphi-red
- deps: update dependency rust to v1.97.0 (#10209) by @renovate[bot]

### ❤️ New Contributors

* @satyamg1620 made their first contribution in [#10211](#10211)

Co-authored-by: shulaoda <[email protected]>