test(push): add fuzz targets for the dimension parsers

[LukasWodka]

The CLI had zero fuzz targets (coverage audit). This fuzzes the user-facing --target-size / --min-size parsers with two invariants that must hold for ANY input (and the fuzzer proves neither panics):

• success ⇒ both dimensions strictly positive;
• error ⇒ both dimensions zero (no partial/garbage pair leaks out).

Seed corpus runs under plain go test; a local -fuzz burst explored 25k+ execs with no failures. No production changes.

🤖 Generated with Claude Code

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Note

Low Risk
Test-only addition with no changes to parser or CLI behavior.

Overview
Adds internal/push/parse_fuzz_test.go with fuzz coverage for the CLI --target-size and --min-size parsers (ParseTargetSize, ParseMinSize).

A shared fuzzWxH helper registers a seed corpus (valid WxH/W,H forms plus malformed and edge-case strings) and checks two invariants on arbitrary input: successful parses must yield strictly positive width and height; failed parses must return (0, 0) with no leaked partial values. The same checks also guard against panics. Seeds run under normal go test; go test -fuzz=... can explore further.

No production code changes—test-only.

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[LukasWodka]

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[saadqbal]

LGTM 👍 Nice — first fuzz targets in the repo, and the two invariants (success⇒positive dims, error⇒(0,0)) match parseWxH's contract exactly. Good seed corpus (overflow, float, whitespace, half-empty pairs).