Update tech_docs/CUE.md

tech_docs/CUE.md

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+Welcome to the world of **CUE** – *Configure-Unify-Execute* – a language that turns the usual “write YAML and pray” workflow into something that feels almost… serendipitous.
+
+In CUE you don’t *imperatively* build configs, websites, DB schemas, or API specs.  
+Instead you **declare** the shape, constraints and defaults you want, then let CUE’s graph-unification engine search the (enormous but finite) space of legal values and hand you back the *one* deterministic result that satisfies every rule.  
+That moment when `cue export` suddenly spits out the exact JSON or SQL DDL you needed? **Deterministic serendipity** – reproducible, cacheable, diff-able.
+
+A 30-second taste:
+
+```cue
+package site
+
+#Page: {
+    title: string & =~"^[A-Z].*"
+    path:  string & =~"^/[a-z0-9/-]+$"
+    meta: {
+        description: string & strings.MinRunes(30) & strings.MaxRunes(160)
+        keywords:    [...string] & list.Unique()
+    }
+}
+
+home: #Page & {
+    title: "Welcome to the World of CUE"
+    path:  "/"
+    meta: keywords: ["cue", "configure", "unify", "execute"]
+}
+```
+
+Run `cue export home` and you get the exact JSON your static-site generator needs, with every constraint already proven.  
+Change a single keyword and CUE re-unifies, yielding a *new* but still deterministic artefact.
+
+The same file can:
+
+* generate OpenAPI specs, Terraform, Kubernetes YAML  
+* validate incoming JSON requests at runtime  
+* spit out SQL DDL and Go structs (`cue get go`) or even HTML via a tiny script
+
+Because CUE merges **types, values and constraints** into one concept, the usual inheritance hell disappears: you compose by *unification* (`&`) instead of copy-paste or fragile overrides.
+
+So yes – in the CUE universe you write a handful of declarations, run `cue`, and the “accidental” correct configuration pops out every single time.  
+Raw deterministic serendipity, no runtime surprises, no “works on my machine”.
+
+---
+
 **CUE (Configure-Unify-Execute)** is an **open-source data constraint language** developed at Google, designed for **configuration management, validation, and templating**. It stands for **Configure, Unify, Execute**.
 
 ### Purpose