feat: support geohash prefix matching for #g filters

[kanishka0411]

Description

Adds support for geohash prefix matching for #g filters.
A query like { "#g": ["u4pruyd*"] } now matches events with geohash tags starting with u4pruyd, for example ["g", "u4pruydqqvj"].
Exact #g filters without * still behave the same as before, so u4pruyd does not match u4pruydqqvj.

Related Issue

Fixes #265

Motivation and Context

Geohash searches usually work with prefixes, especially when a client is looking for events inside a map area.
Before this, Nostream treated #g like any other generic tag filter and only did exact matching. That meant the wildcard form requested in #265, like u4pruyd*, did not match longer geohash values.
This updates both paths that need the behavior:

• stored event queries use LIKE 'prefix%'
• live/in-memory subscription matching uses startsWith

So historical results and live events stay consistent.

How Has This Been Tested?

Added unit tests for:

• wildcard geohash prefix matching
• exact #g matching without wildcard
• generated SQL (LIKE 'prefix%' vs =)
• in-memory event matching

All passing locally.

Screenshots (if appropriate):

Types of changes

• Non-functional change (docs, style, minor refactor)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my code changes.
• I added a changeset, or this is docs-only and I added an empty changeset.
• All new and existing tests passed.

[coveralls]

coverage: 64.097% (+0.08%) from 64.015% — kanishka0411:feat/geohash-prefix-filters into cameri:main

[changeset-bot]

🦋 Changeset detected

Latest commit: b10b02b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
nostream	Patch

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