chore: add typos.toml configuration

[Shinigami92]

The Justfile runs typos as part of just ready, but no typos.toml config exists. This causes typos to exit with code 2 on ~40+ false positives, aborting the just ready workflow for every contributor.

This adds a typos.toml that suppresses the false positives:

• Excludes conformance fixtures (extracted from Angular's own specs, typos are upstream)
• Excludes HTML entity table (entities.rs — spec-defined names like becaus, infintie)
• Excludes e2e comparison fixtures (CSS/HTML test strings)
• Allows standard JS/TS terms (IIFE, xdescribe, xit)
• Allows German i18n test data (Sie, ein, Elemente, alle)
• Allows Angular-specific identifiers and comments (d.ot property binding, mergable from upstream source)

Note: CI does not run typos, so this is purely a local developer experience improvement.