feat(lsp): add PowerShellEditorServices language server

[hashbender]

Summary

Hermes now provides semantic diagnostics for PowerShell files (.ps1 / .psm1 / .psd1) by wiring PowerShellEditorServices into the LSP server registry.

PSES is not a single PATH binary — it's a PowerShell module bundle launched by a pwsh/powershell host via Start-EditorServices.ps1. It ships as a GitHub release zip (no npm/go/pip recipe), so it sits in the manual install tier alongside rust-analyzer and clangd.

Changes

• agent/lsp/servers.py: register the powershell server — extensions, powershell language IDs, a root resolver (PSScriptAnalyzer settings → git workspace), a bundle-locator, and a stdio spawn builder that launches pwsh -NoProfile -NonInteractive ... Start-EditorServices.ps1 -Stdio.
• agent/lsp/install.py: manual-tier recipe so hermes lsp status/list report it (probes the pwsh host).
• website/docs/user-guide/features/lsp.md: supported-servers row + a PowerShell setup section.
• tests/agent/lsp/test_powershell_server.py: 8 tests (routing, language IDs, skip-without-pwsh, skip-without-bundle, command construction, override precedence, bundlePath not leaked into init options).

Bundle resolution order: lsp.servers.powershell.command override → init bundlePath → PSES_BUNDLE_PATH env → <HERMES_HOME>/lsp/PowerShellEditorServices.

Validation

	Result
New tests	8 passed
Full LSP suite	153 passed
E2E (real imports, isolated HERMES_HOME)	.ps1/.psm1/.psd1 route to powershell, spawn command built correctly, lsp status → installed once pwsh found

Infographic

Nous Research

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Mirror-of: NousResearch#55930
NousResearch#55930