docs: show expected output and troubleshooting for the quick start #64

Goal

Let a first-time reader confirm that each quick-start command did the right thing without running it blind, and recover from the most likely first failure (no supported Bash).

Background

Found while walking the repo as a new user at v0.1.0 (7acf3c6). README.md lines 45-76 and docs/five-minute-tutorial.md list commands but never show what they print, so the reader cannot tell key=value output from noise until they run them. Running ./bin/beacon collect --output /tmp/x also prints an unexplained INFO line:

2026-10-08 06:24:33 +0530 INFO /…/vendor/base-bash-libs/lib/bash/file/lib_file.sh:500 Adding section to '/var/folders/…/beacon-support.XXXX/README.txt'

It exposes a vendored-framework file:line and a temp path, and appears only without --quiet; nothing explains it. On a Mac with only /bin/bash 3.2 the launcher exits 1 with "A supported Bash was not found at /opt/homebrew/bin/bash or /usr/local/bin/bash." That message does not say how to fix it, and the docs have no troubleshooting section (no hits for troubleshoot/FAQ/expected output).

Scope

• Add captured, version-neutral expected output for --help, status, plan, collect --dry-run, collect, and verify to the README quick start or tutorial, with the field meanings (framework_provenance=release-artifact, verified=true).
• Explain, or deliberately demote, the framework INFO log line during collect (it is the file module's section-update log from base_file_update_file_section in lib/beacon.sh).
• Add a short Troubleshooting section: unsupported Bash (with the brew install bash remedy and base-bash check), refusing to overwrite an existing --output, and verify failing on a modified bundle.
• Have tests/docs-examples.sh assert the documented output fragments so they cannot drift.

Acceptance Criteria

• A reader can compare their terminal against documented output for every quick-start command.
• The collect log line is either explained in the docs or no longer surprises a first run.
• A Mac user without Homebrew Bash finds the fix from the docs, not by reading launcher source.
• A test fails when documented output no longer matches.

Validation

• ./tests/docs-contracts.sh
• ./tests/docs-examples.sh
• ./tests/validate.sh

Non-Goals

• Do not change Beacon's key=value output contract or exit statuses.
• Do not modify the vendored framework to silence its log.

Project Fields

• Status: Ready
• Priority: P2
• Area: Docs
• Initiative: Base Bash Demo
• Size: M

Agent Assignment

• Assignee: @codeforester