docs(rfd): Add RFDs 084, 085 and five new draft RFDs

[JeanMertz]

Add two new RFDs at Discussion status: RFD 084 (Configurable Markdown
Element Coloring) introduces MarkdownStyleSheet in jp_md to replace
hard-coded SGR escapes with per-element user config under
style.markdown.elements.*, and RFD 085 (Query Explain) adds an
--explain flag to jp query that prints the fully assembled system
prompt, tools, attachments, and request without calling the LLM
provider.

Five new drafts join the backlog: D27 (Granular Recovery for Stored
Conversation Configs) makes the compat layer recover from schema
incompatibilities field-by-field rather than wiping the whole config;
D31 (Transitional JP Protocol Bridge for MCP Tools) bridges
jp_tool::Outcome and _meta."computer.jp/*" into MCP tool execution
ahead of RFD 058; D35 (Loader Namespace and Extends Overrides) moves
loader fields under [loader] and adds entry- scoped extends
exclusion rules; D36 (Live Workspace View for Long-Running Plugin Hosts)
introduces LiveWorkspace<'_> for fresh reads in plugin hosts; and D37
(Conversation Query DSL) proposes a small predicate language for
filtering conversations across jp c ls, jp c grep, jp c rm, and
related commands.

D24 (Stable Event Identifiers) is substantially revised to extend
coverage to ConfigDelta alongside ConversationEvent, rename the
field from id to event_id to avoid collisions with event-
kind-specific id fields, move uniqueness repair out of sanitize into
the storage load path, and add an at(kind, ts) constructor for
synthetic events that must preserve a timestamp.

RFD 070 drops its coupling to RFD 038: ApplyDelta is renamed back to
ConfigDelta throughout, ResetDelta interactions and --cfg NONE/bare---no-cfgalias semantics are stripped, and bare--no-cfg
is defined as rejected at parse time. RFD 004 gains a cross-reference to
RFD 084.

The justfile gains a review recipe that pipes revdiff annotations
into the active jp conversation with the matching git diff attached.
rfd-promote is improved to rewrite relative ../ links and short-form
draft IDs (e.g. bare D27) when a draft is promoted. PR review and
triage recipes now request include_outdated=true when attaching GitHub
reviews.