write the debug protocol page

[carlos-granados]

Replaces the last Reference placeholder. Deliberately short: what DBGp is, where the specification lives, and a note on compatibility.

• leads with the consequence that matters — there is no plugin to install, because any editor that could already debug PHP speaks the protocol already
• points at https://xdebug.org/docs/dbgp for the specification and https://xdebug.org/docs/dbgp-extensions for the extensions this debugger also implements (both checked, 200)
• states DBGp 1.0 with no deliberate differences, which matches DBGP_VERSION "1.0" in src/debugger/handler_dbgp.h — the version announced in the opening message
• closes with an info box saying that leaving the protocol unchanged is a choice for now rather than a commitment, that some improvements are hard to express within the current specification, and that any divergence would be documented here

With this the Reference section is complete: Settings, Functions, Environment Variables, Debug Protocol.

[github-actions]

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2026-09-11 12:23 UTC