build: reclaim bytecode with optimizer runs

[leopoldjoy]

Summary

• lower optimizer runs from 999999 to 10000 to reclaim deployable bytecode headroom
• no Solidity code changes
• preserves the high-run gas profile closely while giving CertManager room for audit hardening

Size measurements

Baseline (optimizer_runs = 999999, forge build --sizes src script):

• CertManager: 24,432 bytes, 144-byte margin
• CertManagerDemo: 24,565 bytes, 11-byte margin
• NitroValidator: 17,275 bytes, 7,301-byte margin

This PR (optimizer_runs = 10000, forge build --sizes src script):

• CertManager: 22,793 bytes, 1,783-byte margin
• CertManagerDemo: 22,926 bytes, 1,650-byte margin
• NitroValidator: 16,157 bytes, 8,419-byte margin

Gas spot checks

Baseline vs this PR:

• test_FullColdAndWarmHintedSequence: 110,555,527 -> 110,689,524 (+0.12%)
• test_HintedValidationRejectsInvalidFinalSignature: 94,587,893 -> 94,721,464 (+0.14%)

For comparison, optimizer_runs = 200 gave more size headroom but raised these paths by ~5-6%, so 10000 is the less disruptive bytecode/gas tradeoff.

Tests

• forge fmt --check src test script
• forge test (204 passed, 1 skipped)
• forge build --sizes src script