docs(output): document EPSS Priority Signal in reading output and HTML report guides

[RohithPariki]

What changed and why

With the introduction of the EPSS Priority Signal (#1067), findings are classified into actionable priority tiers (Fix Now, Fix Soon, Monitor, Low Priority) across terminal output, JSON, and HTML reports.

While cli-reference.md was updated in #1067, reading-output.md and html-report.md were missing documentation for these newly added features and columns:

1. website/docs/reading-output.md:

   • Documented the inline Fix Now badge in compact mode.
   • Updated the findings table guide to explain both EPSS (raw exploitation percentile) and EPSS Priority (four actionable tiers) columns.
   • Updated the 10-minute workflow to reflect prioritizing Fix Now findings first alongside critical/high command groups.

2. website/docs/html-report.md:

   • Documented the interactive findings table's EPSS percentile and EPSS Priority columns.
   • Documented the expanded row detail breakdown for EPSS Priority Signal.
   • Documented the interactive Priority Signal legend rendered beneath the findings table.

Closes #1071

[sonukapoor]

Thanks for picking this up, @RohithPariki - good initiative, and the overall direction is right.

Since this is still a draft, flagging a couple of factual corrections to address before marking it ready:

html-report.md: "highlighted in red for top 10%" is not quite right. The EPSS percentile cell gets a purple/violet highlight for the top 10% threshold - not red. Red is used for the Fix Now badge itself. Worth updating to "highlighted" or "highlighted in purple" to match what actually renders.

reading-output.md: The badge renders as ⚡ Fix Now with no brackets. The [⚡ Fix Now] formatting adds brackets that are not in the actual output - swap to backtick-quoted `⚡ Fix Now` to match exactly.

Minor: "lower exploitation activity" in the Fix Soon and Low Priority tier descriptions is slightly looser than the implementation's "EPSS not in top 10%" - up to you whether to tighten that wording.

[sonukapoor]

All three points addressed - looks accurate now. Merging.

[sonukapoor]

Merged - thank you @RohithPariki!