A memory cut names its real source: FORGE_CELL_MEMORY_MAX_MIB only when set, otherwise the pod's memory.max share #3158

A memory cut now names where its ceiling really came from. The bun test runs for this change pass. The type check did not run: bun x tsc --noEmit failed here with "bun is unable to write files to tempdir: ReadOnlyFileSystem", so the forge's check is the first real type check.

• Source: memoryCeilingSource() already returned env, pod or default, so I reused it instead of changing memoryCeiling()'s return. resolveLimits now records that source as Limits.ceilingFrom.
• Wording: memorySource(source, from) and limitWarnings both use one ceilingText helper.

- env: names FORGE_CELL_MEMORY_MAX_MIB. - pod: says "75% of the pod's memory.max" and does not mention the variable. - default: says "the 4096 MiB default, the host states no memory limit". The issue didn't specify this text, so check the wording.

• Warning line: limitWarnings takes an optional podFile, which lets tests point it at a stand-in memory.max.
• Tests: a new test in test/memory-ceiling.test.ts covers all three sources against stand-in pod files, for both the warning line and the breach summary. I edited two existing tests, because the old wording they asserted was the bug:

- the kill-message test in test/memory-ceiling.test.ts now passes ceilingFrom into memorySource; - the breach-text test in test/check-memory-warning.test.ts now sets ceilingFrom: "env" in its limits.

The issue says this waits for #3135; I did not check whether that pull has landed.

I ran test/memory-ceiling.test.ts, test/check-memory-warning.test.ts and test/settings-check-memory.test.ts, not the whole suite. Nothing in the app's runtime or forge.json changed.

Closes #3145

A memory cut now names where its ceiling really came from. The bun test runs for this change pass. The type check did not run: bun x tsc --noEmit failed here with "bun is unable to write files to tempdir: ReadOnlyFileSystem", so the forge's check is the first real type check.

• Source: memoryCeilingSource() already returned env, pod or default, so I reused it instead of changing memoryCeiling()'s return. resolveLimits now records that source as Limits.ceilingFrom.
• Wording: memorySource(source, from) and limitWarnings both use one ceilingText helper.

- env: names FORGE_CELL_MEMORY_MAX_MIB. - pod: says "75% of the pod's memory.max" and does not mention the variable. - default: says "the 4096 MiB default, the host states no memory limit". The issue didn't specify this text, so check the wording.

• Warning line: limitWarnings takes an optional podFile, which lets tests point it at a stand-in memory.max.
• Tests: a new test in test/memory-ceiling.test.ts covers all three sources against stand-in pod files, for both the warning line and the breach summary. I edited two existing tests, because the old wording they asserted was the bug:

- the kill-message test in test/memory-ceiling.test.ts now passes ceilingFrom into memorySource; - the breach-text test in test/check-memory-warning.test.ts now sets ceilingFrom: "env" in its limits.

The issue says this waits for #3135; I did not check whether that pull has landed.

I ran test/memory-ceiling.test.ts, test/check-memory-warning.test.ts and test/settings-check-memory.test.ts, not the whole suite. Nothing in the app's runtime or forge.json changed.