Add MIT LICENSE and a per-file as-is notice

The repo is public and files are fetched by raw URL, so a reader who lands
on one runbook never sees the README -- the repo's context does not travel
with the file. Each .md now carries two lines under the title, each .ps1 the
equivalent at the end of its .NOTES block.

Deliberately two lines, not a paragraph. These files are read through `| more`
on a client console mid-incident, and the top of the file is where the
procedure-specific warnings live -- never a live chart, stop the service
before copying, confirm authorization before acting. A legal preamble above
those competes with them and trains people to skip past.

Wording aims at a stranger who found the repo, not at the quality of the
procedure: these double as documented-procedure evidence for E&O, and
language implying the content is unreliable works against that.

MIT rather than no license: the warranty and liability disclaimer is the part
that does the work, and leaving it unlicensed makes reuse ambiguous rather
than disclaimed.

Also fixes 5 stale ops/rb URLs in scripts/*.ps1 that the previous commit
missed -- it only swept the .md files.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HwcG1jLs1T425QRMxtjxP7

CONTRIBUTING.md

@@ -51,3 +51,22 @@ Scripts live under `scripts/`. Follow [`scripts/_template.ps1`](scripts/_templat
 - Safe to run via `irm <url> | iex` from our own server.
 - Confirm before anything destructive or that reboots.
 - Check for admin explicitly (`#Requires` is not enforced under `iex`).
+
+## The as-is notice
+
+Every runbook and script carries a short as-is notice — two lines under the `#`
+title in a `.md`, or at the end of the `.NOTES` block in a `.ps1`. Copy it when
+you add a file.
+
+It is per-file rather than README-only for one reason: these are fetched by raw
+URL, so a reader who lands on a single runbook never sees the README or the
+LICENSE. The repo's context does not travel with the file.
+
+Keep it to those two lines. It sits above genuinely important, procedure-specific
+warnings — never a live chart, stop the service before copying, confirm
+authorization before acting — and a longer legal preamble would train people to
+skip the top of the file, which is exactly where those warnings live.
+
+Aim it at a stranger who found the repo, not at the quality of the procedure.
+These runbooks double as documented-procedure evidence; wording that implies the
+content is unreliable works against that.