fix: declare find_dsh_plugins parameters as standard JSON Schema

[245769051-tech]

What & Why

\ind_dsh_plugins\ registers through \ctx.tools.register(), which stores the definition verbatim and projects \parameters\ straight to the model API without compiling the shorthand DSL (only the official \defineTool()\ compiles it).

The shorthand object:

\\js
parameters: {
query: { type: 'string', required: true, ... },
limit: { type: 'number', ... },
}
\\

...has **no top-level \ ype: "object"**, so every model call fails with:

\
INVALID_REQUEST: Invalid schema for function 'find_dsh_plugins':
schema must be a JSON Schema of 'type: object', got 'type: null'
\\

The session drops on the first tool call — effectively disconnecting the agent. Reproduced on dsh 0.1.0-rc.6 (DSH Desktop 2.0.0), headless profile.

Fix

Declare a standard JSON Schema root instead:

\\js
parameters: {
type: 'object',
additionalProperties: false,
properties: { query: {...}, limit: {...}, installable_only: {...} },
required: ['query'],
}
\\

Verification

• Before: isolated headless profile with this plugin crashes with the INVALID_REQUEST above.
• After: same profile boots and answers normally (\Hello! 👋).
• Tool shape check: \parameters.type === 'object',
  equired: ['query'], execute/render intact.