fix(core): validate swipe action parameters

[linhongyu510]

Summary

• require swipe distance and duration to be positive finite numbers
• require repeat to be a non-negative finite integer
• reject end and distance when supplied together
• require direction for distance-based swipes
• preserve the existing repeat=0 safety cap and clarify its description
• add focused schema and runtime regression coverage

Problem

Invalid Swipe parameters could previously produce unexpected device actions:

• negative distance reversed the requested swipe direction
• negative repeat silently executed zero times
• fractional repeat could execute more times than requested
• invalid duration values reached platform adapters
• distance was silently ignored when end was also present

The repeat=0 description also claimed infinite execution, while the implementation intentionally capped it at 10 iterations.

Changes

Validation is applied at two boundaries:

1. the action schema validates model-generated scalar parameters
2. normalizeMobileSwipeParam() validates runtime and direct SDK input

Cross-field constraints remain in the runtime normalization layer so the schema stays a ZodObject and existing locator-field extraction continues to work.

Validation

• Swipe regression suite: 20 tests passed
• device and related planning suite: 6 files, 73 tests passed
• Core build type-check: passed
• Biome: 1605 files passed

[linhongyu510]

Note on the failing checks, in case it factors into review.

This PR's change is confined to packages/core (swipe-parameter validation) with unit coverage in swipe.test.ts and action-description.test.ts. The red checks are all the model-backed / device jobs (e2e-web, chrome-extension-*, android-emulator, ios-simulator, macos/windows-desktop) that need the repository secrets injected on the run — the same external-fork trust/configuration gate, not the changed logic. There is no core unit-test job among the failures.

I confirmed this class of change builds and passes locally on the sibling PR #3068 (packages/core unit file, 33/33). A maintainer can validate via a trusted branch or workflow_dispatch after reviewing the diff; happy to rebase if it helps.