fix(build): Validate platform is arm64 or x86_64 (backport #535)

[mergify]

---

This is an automatic backport of pull request #535 done by [Mergify](https://mergify.com).

[greptile-apps]

Greptile Summary

Backport of #535. Adds an early-exit ValueError in ImageBuilder.__init__ when platform is not "arm64" or "x86_64".

• Validation is placed before self.platform is assigned, which is the correct fail-fast pattern.
• Allowed values match the Literal["arm64", "x86_64"] type annotation already present at line 110.

Confidence Score: 5/5

Single-line guard added to constructor; no logic paths are altered and the validation aligns with the existing type annotation.

The change is a two-line defensive check with no side effects. The allowed values match what the rest of the class already expects and passes to Docker. No edge cases are missed.

No files require special attention.

Important Files Changed

Filename	Overview
agent/builder.py	Adds a ValueError guard validating that platform is "arm64" or "x86_64" before assigning to self.platform; change is correct and consistent with the existing Literal type annotation.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A["ImageBuilder.__init__(platform)"] --> B{"platform in\n('arm64', 'x86_64')?"}
    B -- No --> C["raise ValueError\n'Invalid platform ...'"]
    B -- Yes --> D["self.platform = platform"]
    D --> E["docker buildx build --platform {self.platform}"]

Loading

_{Reviews (1): Last reviewed commit: "fix(build): Validate platform is arm64 o..." | Re-trigger Greptile}