fix(scripts): persist .specify/feature.json during feature creation

[grafvonb]

Description

The current /speckit.specify workflow expects .specify/feature.json to exist, but the shipped create-new-feature scripts do not persist it.

That creates a mismatch between documented behavior and actual script behavior:

• the command flow and downstream tooling expect feature_directory metadata
• feature creation creates the branch and spec directory
• but no .specify/feature.json file is written

As a result, later steps may rely on metadata that the standard feature-creation flow never produces.

This PR fixes that by persisting .specify/feature.json during feature creation in both the Bash and PowerShell scripts. It keeps the change intentionally small and aligns the shipped scripts with the workflow’s existing expectations.

Testing

• Tested locally with uv run specify --help
• Ran existing tests with uv sync && uv run pytest
• Tested with a sample project (if applicable)

Additional verification:

• pytest tests/test_timestamp_branches.py

Results in this environment:

• 44 passed, 6 skipped

The skipped tests are PowerShell runtime tests because pwsh is not available in this environment.

AI Disclosure

• I did not use AI assistance for this contribution
• I did use AI assistance (describe below)

Used Codex to inspect the existing /speckit.specify flow, implement the minimal script changes, and add/update regression tests.

[Copilot]

Pull request overview

This PR aligns the shipped feature-creation scripts with the existing speckit.specify workflow expectation by ensuring .specify/feature.json is created during feature creation (both Bash and PowerShell), and adds regression coverage to prevent the mismatch from recurring.

Changes:

• Persist .specify/feature.json (with feature_directory) when creating a new feature via Bash script.
• Persist .specify/feature.json (with feature_directory) when creating a new feature via PowerShell script.
• Add Bash + PowerShell regression tests asserting the metadata file is written correctly.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
tests/test_timestamp_branches.py	Adds regression tests verifying .specify/feature.json is created and contains the expected feature_directory.
scripts/bash/create-new-feature.sh	Writes .specify/feature.json during non-dry-run feature creation (jq when available, fallback JSON escaping otherwise).
scripts/powershell/create-new-feature.ps1	Writes .specify/feature.json during non-dry-run feature creation and ensures the parent directory exists.
scripts/bash/common.sh	Removes trailing whitespace at EOF (no functional change).
scripts/powershell/common.ps1	Removes trailing whitespace at EOF (no functional change).

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated no new comments.

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