feat: gear button on the Tool Exposure row opens settings pre-selecting the active profile

[dehuaichendragonplus]

Why

The MCP Server window's Tool Exposure row is just a core/full dropdown. The fine-grained, per-tool editing lives in a separate Tool Exposure window that is only reachable through the Funplay/Tool Exposure menu item — not discoverable from the row it actually configures. Worse, that window always opened editing the core list even when full was the active profile, so a user who switched the row to full and then went to customize was silently editing the wrong list.

Approach

• FunplayMCPToolExposurePanel: wrap the existing core/full PopupField and a new gear Button in a horizontal row — the dropdown flex-grows to fill and the gear sits on its right. The gear uses the built-in editor SettingsIcon (d_SettingsIcon on the pro skin) with a ⚙ text fallback if the icon can't be resolved on some editor/skin, plus a tooltip. Clicking opens the Tool Exposure settings window.
• FunplayToolExposureWindow: add a ShowWindow(string editProfile) overload that pre-selects which profile's tool list to edit. It handles both window lifecycles: a freshly-created window (its CreateGUI/BuildUI reads _editingProfile when it builds) and a reused, already-built window (setting the PopupField value fires its change callback, which reloads the tool list). The parameterless ShowWindow() behind the Funplay/Tool Exposure menu item is untouched.
• The gear reads the current MCPToolExportProfile on click, so it always opens editing the list the user is actually using.

New API

• FunplayToolExposureWindow.ShowWindow(string editProfile) — additive overload; the existing parameterless ShowWindow() is unchanged.

Benefits

• One-click access to per-tool exposure editing straight from the row that configures it (discoverability).
• Opening the settings edits the active profile's list, removing the silent "you switched to full but you're editing core" trap.

Test results

Verified in Unity 6000.3.13f1:

• Compiles clean — 0 errors, 0 warnings.
• The gear button renders in the correct position, right of the core/full dropdown (screenshot-verified).
• ShowWindow("full") → the window's _editingProfile and the "Edit Tool List" dropdown are both full, and the header reads Editing full: 157/157 tools (verified by reflection and by screenshot). ShowWindow("core") keeps editing core.
• Opening via the gear invokes the same wired action end-to-end (the settings window opens).

Compatibility

• Purely an editor-UI change — no MCP wire protocol, initialize, or tool-surface change, so it is compatible with every MCP client.
• Additive API (the ShowWindow overload); the menu-item path and all existing window behavior are unchanged.
• Only two files touched, neither shared with any other in-flight PR — merges independently in any order.

Checklist

• Tested in a Unity 2022.3+ project (Unity 6000.3.13f1)
• Verified Funplay > MCP Server opens and the Funplay/Tool Exposure menu item still works
• Did not commit local junk such as .idea/ or .DS_Store
• Updated CHANGELOG.md