fix: reject minification of implicit simple output

[ryanchou1994]

Running echo test | handlebars -m -i- currently exits successfully and prints undefined. An unnamed template implicitly enables simple output, but that happens after the existing simple-output/minification check.

Apply the same check to a single unnamed template before compiling. This reports Unable to minimize simple output with exit status 1 and no stdout, matching explicit --simple --min behavior. Named inline and stdin templates still produce executable minimized output. Existing error precedence is preserved.

Adds real CLI regressions for both input forms, named-minification rendering controls, and a guard-precedence test. The two new rejection tests fail on the original code.

Validation: Linux build, lint and default test suite pass (655 passed, 27 skipped; coverage thresholds pass). The Mac suite also passes with command-scoped init.defaultBranch=master to match existing Git test fixtures; lint passes. Separate integration/browser/Windows matrices were not run locally.

Refs #1525. This does not add minification support for unnamed simple output.

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[ryanchou1994]

Hi @jaylinski, friendly ping: the workflows on this PR are still waiting for approval to run. Happy to adjust anything if needed. Thanks!