feat(flutter): derive OPEN_RUNTIMES_BUILD_KEYS from user variables

[jaysomani]

Captures user-supplied variable keys before executor merges its own internal vars, then adds OPEN_RUNTIMES_BUILD_KEYS as a space-separated list.

[greptile-apps]

Greptile Summary

Captures user-supplied variable keys before executor-owned variables are merged, then provides those keys to runtime builds through OPEN_RUNTIMES_BUILD_KEYS.

• Adds controller logic to serialize user variable names as a space-separated environment value.
• Adds an end-to-end Node v5 test confirming the user key is available during the build and the internal secret key is excluded in the ordinary non-collision case.

Confidence Score: 5/5

The PR appears safe to merge based on the reviewed changes, with no concrete actionable failure established.

The controller preserves the intended distinction between user-supplied keys and executor-added variables, and the end-to-end test verifies the primary v5 build path without revealing a blocking defect.

Important Files Changed

Filename	Overview
app/controllers.php	Captures the original request variable names and injects them as OPEN_RUNTIMES_BUILD_KEYS after merging executor-owned environment variables.
tests/e2e/ExecutorTest.php	Adds end-to-end coverage showing a user variable key reaches the build environment without including the ordinary internal secret key.

_{Reviews (1): Last reviewed commit: "feat(flutter): derive OPEN_RUNTIMES_BUIL..." | Re-trigger Greptile}