feat(migration): add McpServerMigrator for v2 data migration

[DeJeune]

What this PR does

Before this PR:

MCP server configurations (user-installed and builtin servers) are stored only in Redux (localStorage), with no SQLite migration path for the v2 architecture.

After this PR:

MCP server data is migrated from Redux state.mcp.servers into a new mcp_server SQLite table as part of the v2 migration pipeline. Runtime flags (isUvInstalled, isBunInstalled) are intentionally skipped as they are re-detected at startup.

Why we need it and why it was done in this way

This is part of the v2 data layer refactoring that replaces Redux with SQLite. The MCP server configuration is user data that must be preserved across the migration.

The following tradeoffs were made:

• All 28 MCPServer fields are mapped 1:1 to SQLite columns (no renames) to keep the migration simple and reversible.
• JSON columns (text({ mode: 'json' })) are used for complex fields (args, env, headers, tags, etc.) rather than normalized tables, matching the existing data shape.
• Runtime detection flags (isUvInstalled, isBunInstalled) are excluded since they belong in CacheService.

The following alternatives were considered:

• Normalizing array/object fields into separate tables — rejected as over-engineering for this data volume.

Breaking changes

None. This is a migration-only change with no impact on existing functionality.

Special notes for your reviewer

• The ReduxExporter.SLICES_TO_EXPORT was missing 'mcp', which caused the MCP slice to never be exported to Main process. This was a gap in the existing migration infrastructure that this PR fixes.
• The v2-migrator skill has been updated to include the ReduxExporter registration step in its checklist.
• 17 new tests cover transform functions (6) and migrator phases (11).

Checklist

• PR: The PR description is expressive enough and will help future contributors
• Code: Write code that humans can understand and Keep it simple
• Refactor: You have left the code cleaner than you found it (Boy Scout Rule)
• Upgrade: Impact of this change on upgrade flows was considered and addressed if required
• Documentation: A user-guide update was considered and is present (link) or not required. Check this only when the PR introduces or changes a user-facing feature or behavior.
• Self-review: I have reviewed my own code (e.g., via /gh-pr-review, gh pr diff, or GitHub UI) before requesting review from others

Release note

NONE

[EurFelux]

Note

This issue/comment/review was translated by Claude.

The settings table also stores MCP servers pulled from the cloud of various providers, consider how to handle this

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Original Content

settings表中还储存了从各个provider云端拉取的mcp servers，考虑一下如何处理吧

[DeJeune]

Note

This issue/comment/review was translated by Claude.

I can't find the relevant code, I have MCP servers pulled from the cloud in this table

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Original Content

我搜不到相关代码，我现在这个表中就有云端拉取的mcp servers

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The settings table also stores MCP servers pulled from the cloud of various providers, consider how to handle this

[EurFelux]

cherry-studio/src/renderer/src/pages/settings/MCPSettings/McpProviderSettings.tsx

Line 106 in 699682e

await db.settings.put({ id: dbKey, value: servers })

Note

This issue/comment/review was translated by Claude.

This data is all in the cloud. We can fetch it again even without migration, so it's not a big issue.

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Original Content

这部分数据都在云端，不迁移也可以再fetch一次，倒是问题不大

[DeJeune]

Note

This issue/comment/review was translated by Claude.

ok, please submit a new pr

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Original Content

ok，重新提个pr吧