docs: Broken compare links in CHANGELOG.md files

## Description

Several compare links in the CHANGELOG.md files return 404 errors. These appear to be auto-generated by release tooling and reference old tag naming conventions.

## Broken Links

### packages/bedrock-sdk/CHANGELOG.md
- `https://github.com/anthropics/anthropic-bedrock-typescript/compare/v0.0.1...v0.1.0` (old repo name)
- `https://github.com/anthropics/anthropic-sdk-typescript/compare/bedrock-sdk-v0.20.0...bedrock-sdk-v0.21.0`
- `https://github.com/anthropics/anthropic-sdk-typescript/compare/bedrock-sdk-v0.7.0...bedrock-sdk-v0.7.1`

### packages/foundry-sdk/CHANGELOG.md
- `https://github.com/anthropics/anthropic-sdk-typescript/compare/foundry-sdk-v0.1.0...foundry-sdk-v0.2.0`

### CHANGELOG.md (root)
- `https://github.com/anthropics/anthropic-sdk-typescript/compare/sdk-v0.12.3...sdk-v0.12.4`
- `https://github.com/anthropics/anthropic-sdk-typescript/compare/sdk-v0.41.0...sdk-v0.42.0`

### packages/vertex-sdk/CHANGELOG.md
- `https://github.com/anthropics/anthropic-sdk-typescript/compare/vertex-sdk-v0.0.1...vertex-sdk-v0.1.0`
- `https://github.com/anthropics/anthropic-sdk-typescript/compare/vertex-sdk-v0.10.0...vertex-sdk-v0.11.0`

## Root Cause

The tags referenced in these compare links don't exist. This could be due to:
1. Tag naming convention changes
2. Repository rename from `anthropic-bedrock-typescript` to monorepo structure
3. Release tooling configuration

## Suggested Fix

Update the release tooling configuration to generate correct compare URLs, or manually fix the historical CHANGELOG entries.

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🤖 Generated with [Claude Code](https://claude.com/claude-code)