docs: strip reader-useless implementation-leak phrasing

[abrichr]

What

Sweep across all authored docs.openadapt.ai pages to remove implementation-leak / internal-plumbing phrasing that is useless to a reader, rewriting to reader-facing value. Trigger example was on /get-started/what-works-today/:

OpenAdapt Hosted has a public $500/month browser-workflow subscription backed by the configured live Stripe Product and Price.

The bolded part describes our internal wiring and means nothing to a user. It now reads: "OpenAdapt Hosted has a public $500/month browser-workflow subscription."

Changes (old -> new)

• get-started/what-works-today.md
  • "subscription backed by the configured live Stripe Product and Price" -> "subscription." (keeps $500/month + pre-payment-trial evidence)
  • "A non-simulated Modal session on openadapt-flow 1.8.0" -> "A non-simulated hosted browser session on openadapt-flow 1.8.0" (internal vendor name; all evidence retained)
• guides/hosted.md
  • "Stripe is the commercial source of truth. The website retrieves the live offer server-side and Checkout confirms the same Product and Price before payment." -> "Payment runs through Stripe, and the price shown on the website is the exact price you pay at Checkout."
  • "A qualified Modal browser session" -> "A qualified hosted browser session"
  • "Live mode uses the configured authentication, database, object storage, runner, callback secrets, and billing services." -> "Live mode uses real authentication, database, object storage, runner, and billing services." (keeps the fails-closed contrast)
• concepts/deployment-matrix.md
  • "Stripe Checkout using the configured product and price;" -> "Stripe Checkout for the public subscription;"
  • "The configured Stripe offer is the commercial source of truth." -> "Stripe is the commercial source of truth for pricing."
• concepts/substrate-model.md
  • dropped internal "provisioned by the existing oa-vm tooling"; kept the QEMU/KVM + Apache Guacamole architecture (reader-useful)
• guides/deploy-on-prem.md
  • "One config wires the deployment" / "A production run is wired by a single" -> "One config drives the deployment" / "A production run is defined by a single"
• guides/induce-a-program.md
  • "effects, actuation, and durability are wired." -> "... are all configured."

Deliberately left as evidence, not plumbing

• All pinned substrate-evidence copy in what-works-today.md (Windows/macOS/RDP run counts, oracle results, commit hashes, Flow PR numbers, Supported/scoped markers) enforced by test_substrate_evidence_copy.py and validate_docs.py.
• Reader-useful config the user can act on: env var names (OPENADAPT_INGEST_TOKEN, etc.), OS-keychain resolution order, deployment.yaml, CLI --host/--token defaults referencing the user's configured values.
• Security posture that substantiates claims: ingest-token/HMAC semantics in security-review.md and hosted.md, signed-webhook activation in the first-customer evidence narrative.
• "signed-webhook activation" left in place as part of the credibility/evidence chain (borderline evidence vs plumbing).

Guards

mkdocs build --strict, python scripts/validate_docs.py, and pytest tests/ (64 passed) all green.

🤖 Generated with Claude Code

https://claude.ai/code/session_01NyCHrzA1psrKMFfroYbzaM