Build realistic test fakes at run time; add narrow secret-scan configs

[imanimanyara]

Two commits.

Test fakes. Two dataset values read to secret scanners as high-entropy secrets:

• tests/Rules/TrailingNewlineTest.php: the JWT row now comes from a trailingNewlineJwt() helper that assembles header, payload and signature from their claims, the same way IdentifiersRulesTest builds its tokens. The result is byte-identical to the old literal.
• tests/Rules/Crypto/CryptoRulesTest.php: the mixed-case bech32 row is derived from the lower-case vector with str_replace, which also states what the case is testing.

Narrow configs. .gitguardian.yaml and .gitleaks.toml ignore only tests/Fixtures/**/*, and both are export-ignored.

secret_scan.py check --ref HEAD returns 0. Local gates: pint and rector pass; the two changed test files pass (50 tests). The full suite passed apart from the two activeUrl tests, which need DNS and could not resolve in the local sandbox. phpstan could not start locally (sandbox /tmp restriction), so CI is the phpstan gate here.

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.

[github-actions]

Benchmark results

Scenario	Optimizations	Native Laravel	Optimized	Speedup	Δ vs base
Product import — 500 items, simple rules	Wildcard, fast-check	96.1ms	1.7ms	~57x	+0%
Nested order lines — 1000 orders × 5 line items	Wildcard, fast-check (nested)	449.8ms	9.7ms	~46x	+2%
Event scheduling — 100 items, field-ref dates	Wildcard, partial fast-check	15.2ms	0.7ms	~22x	+0%
Article submission — 50 items, custom Rule objects	Wildcard only	5.5ms	1.5ms	~4x	+0%
Conditional import — 100 items, 47 conditional fields	Wildcard, pre-evaluation	119.5ms	27.8ms	~4x	+0%
Login form — 3 fields, no wildcards	Fast-check (flat)	0.1ms	0.0ms	~9x	—