fix(matcher): add workaround hint to invalid params warning

[shanliuling]

What is the problem?

When using a catch-all route with a named redirect like:

{
  path: '/:pathMatch(.*)*',
  redirect: { name: 'HOME' }
}

Users see a warning:
Discarded invalid param(s) "pathMatch" when navigating.

The warning message doesn't explain how to fix the issue.

How did I fix it?

Enhanced the warning message to include a helpful workaround hint:
If you are using a catch-all route with a named redirect, pass an empty params object: redirect: { name: '...', params: {} }.

This matches the workaround suggested by @posva in the issue comments.

How was this tested?

• Updated the existing test in packages/router/__tests__/warnings.spec.ts to match the new warning format
• The test now also checks for the presence of the workaround hint

Closes #1617

Summary by CodeRabbit

Release Notes

• Bug Fixes
  • Improved warning messages for invalid route parameters to include additional guidance about catch-all routes and parameter handling, helping developers resolve configuration issues more effectively.

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[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: ee3a5f41-7bb3-4154-a512-b1e33fe666a6

📥 Commits

Reviewing files that changed from the base of the PR and between 47f0334 and e5667ca.

📒 Files selected for processing (2)

• packages/router/__tests__/warnings.spec.ts
• packages/router/src/matcher/index.ts

---

📝 Walkthrough

Walkthrough

The changes enhance the warning message displayed when invalid parameters are discarded during navigation to catch-all routes with named redirects. A test expectation is updated to verify the improved warning guidance is correctly emitted.

Changes

Cohort / File(s)	Summary
Warning Message Enhancement packages/router/src/matcher/index.ts	Updated the invalid params warning to include additional guidance about catch-all routes with named redirects and an example of passing an empty params object.
Test Update packages/router/__tests__/warnings.spec.ts	Removed trailing whitespace from expected warning string and added new expectation to verify the catch-all route workaround hint is displayed.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~5 minutes

Poem

A catch-all route hops with delight,
No more warnings blocking its flight,
With hints now clear, like carrots so bright,
The path forward guides users right! 🐰✨

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly describes the main change: adding a workaround hint to the invalid params warning message for the catch-all route scenario.
Linked Issues check	✅ Passed	The PR successfully addresses issue #1617 by enhancing the warning message with a workaround hint and updating tests to validate the new message format.
Out of Scope Changes check	✅ Passed	All changes are directly related to the objective: modifying the warning message in matcher/index.ts and updating corresponding tests in warnings.spec.ts.

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📝 Coding Plan

• Generate coding plan for human review comments

---

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