fix: parse boolean query params from strings

[yoreley777]

Purpose

Needed for TOOL-5054 (single observation search in Vertex). Boolean keywords like jointObservation arrive as strings in the request, and bool("false") is True, so jointobservation=false returned the same results as true. Kim suggested handling this in SearchAPI with the string_to_obj_map.

Description

Added a small string_to_bool and mapped bool to it in string_to_obj_map, so "true"/"false" (any case) are parsed correctly for jointObservation and collectionAlias. Other strings (like "asdf") now return a 400 instead of quietly becoming true. No packaging changes, no new endpoints.

Snippet

curl 'http://127.0.0.1:8080/services/search/param?dataset=NISAR&processinglevel=RSLC&output=count&jointobservation=false'

Before: same count as jointobservation=true (20272). After: 118427 (no filter is 138699, so joint + single add up).

jointobservation=asdf now returns 400 {"error": {"type": "ERROR", "report": "ValueError('Invalid boolean: asdf')"}}.

Error/Warning/Regression Free

Checked locally with the app for GET, POST and output=python (the script now shows "jointObservation": False).

Unit Tests

Added tests/unit/test_asf_opts.py (3 tests) and two yml cases: 200 with "false" and 400 with "asdf".

Target Merge Branch

test

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Checklist

• Purpose
• Description
• Snippet
• Error/Warning/Regression Free
• Unit Tests
• Target Merge Branch