[AI Bundle] Preserve boolean options in agent/vectorizer model confguration

[sonnymilton]

Q	A
Bug fix?	no
New feature?	yes
Docs?	no
Issues	-
License	MIT

Problem

When configuring models in symfony/ai-bundle via the options section, boolean values were misrepresented.
This happens because http_build_query() converts booleans into integers:

• true → 1
• false → 0

So configuration like:

ai:
  agent:
    my_agent:
      model:
        name: gpt-4o-mini
        options:
          stream: false

Converted to gpt-4o-mini?stream=0
Expected: gpt-4o-mini?stream=false

This makes it impossible to distinguish between a booleans and an integers during parsing.

Changes

• Inline normalization of options before calling http_build_query(). Booleans are explicitly converted to the strings "true" / "false".
• Added regression tests for both agents and vectorizers.

[OskarStark]

Good catch, thanks @sonnymilton.