feat: el-ide — native IDE for engram-lang, LSP, type graph, plugin ecosystem

Axum HTTP server (port 7771) serving a single-page IDE with CodeMirror 6
syntax highlighting for engram-lang, a force-directed type graph visualizer,
LSP (completions, hover, diagnostics), SSE-streamed build/run output, a
plugin host with five first-party plugins, and a reasoning panel that proxies
to engram-server. 28 tests across three crates, zero warnings.

Cargo.toml

@@ -0,0 +1,40 @@
+[workspace]
+members = [
+    "crates/el-ide-server",
+    "crates/el-lsp",
+    "crates/el-plugin-host",
+]
+resolver = "2"
+
+[workspace.package]
+version = "0.1.0"
+edition = "2021"
+license = "MIT"
+authors = ["Neuron Technologies"]
+
+[workspace.dependencies]
+# Internal crates (el-ide workspace)
+el-lsp         = { path = "crates/el-lsp" }
+el-plugin-host = { path = "crates/el-plugin-host" }
+
+# Engram lang crates (path deps)
+el-lexer    = { path = "../engram-lang/crates/el-lexer" }
+el-parser   = { path = "../engram-lang/crates/el-parser" }
+el-types    = { path = "../engram-lang/crates/el-types" }
+el-compiler = { path = "../engram-lang/crates/el-compiler" }
+
+# External
+serde       = { version = "1", features = ["derive"] }
+serde_json  = "1"
+thiserror   = "2"
+tokio       = { version = "1", features = ["full"] }
+axum        = { version = "0.7", features = ["macros"] }
+tower-http  = { version = "0.5", features = ["cors", "fs"] }
+rust-embed  = { version = "8", features = ["axum"] }
+tracing             = "0.1"
+tracing-subscriber  = { version = "0.3", features = ["env-filter"] }
+reqwest             = { version = "0.12", features = ["json"] }
+async-stream        = "0.3"
+tokio-stream        = "0.1"
+which               = "6"
+mime_guess          = "2"