Bundle mappings.wasm locally instead of loading it from unpkg

[rmuratov]

Closes #29

What

SourceMapConsumer.initialize was pointing at https://unpkg.com/source-map@0.7.6/lib/mappings.wasm. The wasm file is now imported via Vite's ?url asset import and served from our own origin (dist/assets/mappings-*.wasm, ~48 kB / 18.7 kB gzip).

Why

• The app claims to run entirely client-side, but broke offline, behind corporate proxies, or whenever unpkg was down.
• Removes a third-party dependency from a tool where users paste potentially sensitive source maps.
• The wasm version can no longer drift from the installed source-map package version.

Changes

• src/main.tsx — import source-map/lib/mappings.wasm?url and pass the bundled URL to initialize.
• src/vite-env.d.ts — module declaration for *.wasm?url imports.
• src/__tests__/main.test.tsx — test that the entry point initializes the consumer with a local (non-http) wasm URL.

Verification

• All 23 tests pass; tsc, eslint, prettier, and the production build are clean.
• Verified the production build in Chrome against vite preview: pasted a stack trace and a fixture source map, the trace resolved to original positions, and the network panel shows mappings-Dhu04MXZ.wasm served from localhost with no requests to unpkg.

🤖 Generated with Claude Code

[cloudflare-workers-and-pages]

Deploying sourcemap-tools with    Cloudflare Pages

Latest commit:	f592b88
Status:	✅  Deploy successful!
Preview URL:	https://e21b7fa2.sourcemap-tools.pages.dev
Branch Preview URL:	https://bundle-mappings-wasm.sourcemap-tools.pages.dev

View logs

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (ce8c959) to head (f592b88).

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #34   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            9         9           
  Lines          203       203           
  Branches        49        49           
=========================================
  Hits           203       203           

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