Separate sql query builder & yaml parser package

[spwoodcock]

What type of PR is this?

• 🍕 Feature
• 🐛 Bug Fix
• 📝 Documentation
• 🧑‍💻 Refactor
• ✅ Test
• 🤖 Build or CI
• ❓ Other (please specify)

Related Issue :

Fixes #302

What does this PR do ?

• As described in the issue, it would be useful for other tools to use the osm2pgsql SQL query builder here.
• We also need the osm-raw-data YAML / JSON format parsing to feed in.
• This PR moves the logic of parsing + query building to a separate package, that could be published standalone.
• The builder and models are refactored in the code to use the new package.
• The package will then be used as the basis for both raw-data-api and PostPass querying (which both use osm2pgsql db format).

Note

This PR basically just pulls out the existing builder.py logic verbatim, into a new file (in the standalone package).
It then attempts to wrap the extracted functionality in builder.py under ./src.
Hopefully nothing changed in the raw-data-api functionality as a result 🤞

How to test ?

• This is where I really need a bit of help.
• I can test the query builder logic works with a few unit tests.
• But its hard to run the integration tests for the full raw-data-api stack, without ingesting an OSM database etc - setting this up locally.

AI Assistance

• Yes
• Model: Opus 4.6 LLM to help plan this, implement unit tests, and sanity check / review the implementation.

Checklist before requesting review :

• 📖 Read the HOT Code of Conduct: https://docs.hotosm.org/code-of-conduct
• 👷‍♀️ Create small PRs. In most cases, this will be possible.
• ✅ Provide tests for your changes.
• 📝 Use descriptive commit messages.
• 📗 Update any related documentation and include any relevant screenshots.

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