chore: add unicoder.yaml with VGV preset

[erickzanardo]

Adds a unicoder.yaml so the Unicoder bot configures this repo from the branch itself, using the VGV Best Practices preset:

• SDK: Flutter "3.47", which resolves to the newest 3.47.x patch. That's the same line CI pins (flutter_version: "3.47.x" in .github/workflows/example.yaml). The bot doesn't accept the .x suffix, so the major.minor form is used instead.
• Tool: Very Good CLI 1.5.0 (latest).
• Claude plugins: vgv-ai-flutter-plugin and vgv-wingspan from VeryGoodOpenSource/very-good-claude-code-marketplace.

Each section the file declares replaces the dashboard's value for that section, and sections it leaves out (such as hooks) keep their dashboard values. Very Good Blueprints is part of the preset but can't be set from the file, so it stays in the dashboard.

Also adds unicoder to the cspell words, so the new file and this PR title pass the spell check.

When CI moves to a new Flutter version, update the version here to match.

🤖 Generated with Claude Code

[unicoderbot]

I'll review the code and share my feedback shortly.

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Code review submitted.

[unicoderbot]

This is a small, well-documented configuration PR that adds a unicoder.yaml bot config using the VGV Best Practices preset, plus a cspell dictionary entry. The YAML is clean and the key choices are sound:

Positives

• version: "3.47" is correctly quoted, avoiding YAML interpreting it as a float, and aligns with the flutter_version: "3.47.x" pin in .github/workflows/example.yaml (both resolve to the newest 3.47.x patch).
• The very_good_cli tool and the two Claude plugins/marketplace are declared consistently.
• The PR description clearly explains the per-section override semantics and the CI-version coupling.

Minor observation

• The stated rationale for adding unicoder to the cspell words does not appear to hold: the spell-check workflow only scans **/*.md (includes: **/*.md), so unicoder.yaml is never spell-checked, and the word unicoder does not appear in any markdown file in the repo. The cspell entry is therefore harmless but likely unnecessary unless a future .md file (or a changed spell-check scope) references it.

No correctness, security, or lifecycle issues found. Approvable as-is; the cspell note is optional cleanup.

[unicoderbot]

All my review comments have been resolved. Approving this PR. If another review is needed, just re-request it.