fix(ollama): preserve tools across agent turns

[iwasatapex]

Description

Fix Ollama tool handling in Continue Agent mode.

The Ollama adapter previously attached tool definitions only when the last message had role user. After a tool call, the next request contains a tool message as the latest message, so Continue stopped sending the tool definitions back to Ollama.

This caused multi-step agent loops to fall back to textual/XML tool calls instead of structured tool calls, which could stall or break the agent loop.

What changed

• Always attach configured tools to Ollama chat requests.
• Removed the incorrect requirement that the last message must have role user.
• Added regression tests covering:
  • first-turn tool attachment
  • continuation after a tool result
  • multiple tool calls in the same agent loop

Testing

The Ollama regression tests were added and run successfully against the patched source.

The fix was also packaged and tested with Continue 2.0.0 in a local VSCodium installation.

The patched installation successfully handled multi-step sequences including:

read → edit → read → verify

and additional sequential tool calls without falling back to raw textual/XML tool syntax.

Scope

Only the Ollama tool-calling path and its regression tests are changed.

No unrelated package/version changes are included.