refactor: remove ESBuildContextManager from app-event-watcher

[isaacroldan]

We originally added ESBuildContextManageras a faster way to re-build UI extensions -> by keeping in memory esbuild contexts, re-builds are faster.

This was at the expense of having a custom build pipeline in the app watcher just for ui extensions. This is now causing issues because ui-extensions are not following the standard build flow and therefore not running all "build steps".

This PR removes ESBuildContextManagerand brings back ui-extensions to be compiled like the rest of extensions:

• Simplifies the dev watcher pipeline — one build path instead of two.
• Reduces surface area — ~375 lines of code and tests deleted.
• Makes the watcher easier to reason about — no need to track which extensions use esbuild contexts vs. the default build path.

The benefit of this manager is negligible for small extensions (we might save single digit miliseconds)

[isaacroldan]

• refactor: remove ESBuildContextManager from app-event-watcher #7252 👈 (View in Graphite)
• main

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[Copilot]

Pull request overview

Removes the custom esbuild-context-based build path from the app dev watcher so UI extensions go through the same “standard” build pipeline (and therefore run the same build steps) as other extension types.

Changes:

• Deleted ESBuildContextManager and its dedicated tests.
• Simplified AppEventWatcher to always build extensions via extension.buildForBundle().
• Updated watcher tests to no longer mock/inject the esbuild manager and to simulate errors via the standard build path.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
packages/app/src/cli/services/dev/app-events/app-watcher-esbuild.ts	Removed the custom esbuild context manager implementation.
packages/app/src/cli/services/dev/app-events/app-watcher-esbuild.test.ts	Removed tests tied to the esbuild context manager behavior.
packages/app/src/cli/services/dev/app-events/app-event-watcher.ts	Dropped the esbuild-manager branch and unified extension builds under buildForBundle().
packages/app/src/cli/services/dev/app-events/app-event-watcher.test.ts	Updated tests to match the unified build path; removed esbuild-manager mocking.

Comments suppressed due to low confidence (5)

packages/app/src/cli/services/dev/app-events/app-event-watcher.test.ts:404

• There’s trailing whitespace on this blank line, which will likely fail formatting/linting (Prettier/no-trailing-spaces). Please remove the spaces so it’s an empty line.

          if (needsAppReload) {

packages/app/src/cli/services/dev/app-events/app-event-watcher.test.ts:441

• There’s trailing whitespace on this blank line, which will likely fail formatting/linting (Prettier/no-trailing-spaces). Please remove the spaces so it’s an empty line.

        // Then

packages/app/src/cli/services/dev/app-events/app-event-watcher.test.ts:478

• There’s trailing whitespace on this blank line, which will likely fail formatting/linting (Prettier/no-trailing-spaces). Please remove the spaces so it’s an empty line.

    })

packages/app/src/cli/services/dev/app-events/app-event-watcher.test.ts:512

• There’s trailing whitespace on this blank line, which will likely fail formatting/linting (Prettier/no-trailing-spaces). Please remove the spaces so it’s an empty line.

    })

packages/app/src/cli/services/dev/app-events/app-event-watcher.test.ts:603

• There’s trailing whitespace on this blank line, which will likely fail formatting/linting (Prettier/no-trailing-spaces). Please remove the spaces so it’s an empty line.

          type: 'file_updated',

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[Copilot]

With the ESBuildContextManager path removed, UI extensions now build via extension.buildForBundle(). The UI bundling step (buildUIExtension) currently catches esbuild failures and rethrows an AbortError without preserving the original error.errors payload, so this watcher’s esbuild-specific formatting branch won’t run and users may only see a generic message. Consider propagating the underlying esbuild errors array on the thrown error (similar to buildFunctionExtension) so dev watcher output remains actionable.