[rchl]

Since #2765, project settings can override custom top-level settings of LSP-* packages (for example "binary" in LSP-clangd). The project schema still validated every settings.LSP.* key against the strict ClientConfig definition ("additionalProperties": false), so those settings were reported as Property binary is not allowed.

The package's own project schema (which defines those settings) doesn't help here: the JSON server combines schemas contributed by different packages with allOf, and each branch is validated independently, so LSP's branch can't know about properties defined by the package.

Changes:

• Validate settings.LSP keys matching ^LSP- against the lenient LSP-plugin-base schema. Common settings are still validated and completed; package-specific settings are left to the schema contributed by the package. Other keys (servers defined in the project) keep using the strict ClientConfig.
• Add tcp_port (the only ClientConfig property missing there) to LSP-plugin-base, through a shared ClientTcpPort definition.

Packages can opt-in to reporting unknown keys by combining LSP-plugin-base with their own definitions and "unevaluatedProperties": false:

"LSP-clangd": {
  "allOf": [
    { "$ref": "sublime://settings/LSP-plugin-base" },
    { "$ref": "sublime://settings/LSP-clangd#/definitions/PluginConfig" }
  ],
  "unevaluatedProperties": false
}

Checked with vscode-json-languageservice (6.0.0-next.2, as used by LSP-json):

File	Before	After
project with LSP-clangd → binary/system_binary	not allowed	no diagnostics
project-only server with typo commnd	not allowed	not allowed
LSP-clangd override with "selector": 42	incorrect type	incorrect type
LSP.sublime-settings client with "tcp_port": "nope"	incorrect type	incorrect type
LSP-clangd.sublime-settings with "tcp_port": "nope"	not validated	incorrect type