docs: rename diagram assets to doc-prefixed scheme, update exports

Asset renames (matching the new Nextcloud source naming convention —
doc name first, then description):
- architecture-trust-depth.svg -> architecture-overview-trust-depth.svg
- firewall-docker-bypass.svg -> firewall-and-network-docker-bypass.svg
- secrets-lifecycle.svg -> secrets-and-pki-lifecycle.svg
- trust-boundaries-blast-radius.svg -> readme-trust-boundaries-blast-radius.svg
Updated all 4 markdown references accordingly.

Also refreshed diagram exports (secret-distribution-flows.svg, and the
4 renamed ones) with today's fixes, and folded in the earlier pending
sso-and-identity.md work: precise live-verified native-OIDC app list
(12 apps, not ~9), the Proxmox no-Proxy-Provider exception, real API
evidence for it, and the automation-bot migration story.

assets/secrets-and-pki-lifecycle.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!-- Do not edit this file with editors other than draw.io -->
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<svg xmlns="http://www.w3.org/2000/svg" style="background: transparent; background-color: transparent; color-scheme: light dark;" xmlns:xlink="http://www.w3.org/1999/xlink" version="1.1" width="1312px" height="420px" viewBox="0 0 1312 420" content="&lt;mxfile host=&quot;embed.diagrams.net&quot; scale=&quot;1&quot; border=&quot;0&quot;&gt;&#10;  &lt;diagram name=&quot;Secret Lifecycle&quot; id=&quot;secret-lifecycle-1&quot;&gt;&#10;    &lt;mxGraphModel dx=&quot;1414&quot; dy=&quot;791&quot; grid=&quot;1&quot; gridSize=&quot;10&quot; guides=&quot;1&quot; tooltips=&quot;1&quot; connect=&quot;1&quot; arrows=&quot;1&quot; fold=&quot;1&quot; page=&quot;1&quot; pageScale=&quot;1&quot; pageWidth=&quot;1340&quot; pageHeight=&quot;620&quot; math=&quot;0&quot; shadow=&quot;0&quot;&gt;&#10;      &lt;root&gt;&#10;        &lt;mxCell id=&quot;0&quot; /&gt;&#10;        &lt;mxCell id=&quot;1&quot; parent=&quot;0&quot; /&gt;&#10;        &lt;mxCell id=&quot;agent&quot; parent=&quot;1&quot; style=&quot;rounded=1;whiteSpace=wrap;html=1;fillColor=#e1d5e7;strokeColor=#9673a6;fontColor=#333333;fontSize=14;fontStyle=1;shadow=1;&quot; value=&quot;Vault Agent&amp;lt;br&amp;gt;&amp;lt;font style=&amp;quot;font-size:11px&amp;quot;&amp;gt;runs on the consuming host&amp;lt;/font&amp;gt;&quot; vertex=&quot;1&quot;&gt;&#10;          &lt;mxGeometry height=&quot;90&quot; width=&quot;200&quot; x=&quot;40&quot; y=&quot;260&quot; as=&quot;geometry&quot; /&gt;&#10;        &lt;/mxCell&gt;&#10;        &lt;mxCell id=&quot;vault&quot; parent=&quot;1&quot; style=&quot;rounded=1;whiteSpace=wrap;html=1;fillColor=#e1d5e7;strokeColor=#9673a6;fontColor=#333333;fontSize=14;fontStyle=1;shadow=1;&quot; value=&quot;Vault&amp;lt;br&amp;gt;&amp;lt;font style=&amp;quot;font-size:11px&amp;quot;&amp;gt;server&amp;lt;/font&amp;gt;&quot; vertex=&quot;1&quot;&gt;&#10;          &lt;mxGeometry height=&quot;90&quot; width=&quot;200&quot; x=&quot;380&quot; y=&quot;260&quot; as=&quot;geometry&quot; /&gt;&#10;        &lt;/mxCell&gt;&#10;        &lt;mxCell id=&quot;disk&quot; parent=&quot;1&quot; style=&quot;shape=cylinder3;whiteSpace=wrap;html=1;fillColor=#F5F5F5;strokeColor=#666666;fontColor=#333333;fontSize=14;fontStyle=1;shadow=1;boundedLbl=1;&quot; value=&quot;Local Disk&amp;lt;br&amp;gt;&amp;lt;font style=&amp;quot;font-size:11px&amp;quot;&amp;gt;rendered file&amp;lt;/font&amp;gt;&quot; vertex=&quot;1&quot;&gt;&#10;          &lt;mxGeometry height=&quot;110&quot; width=&quot;160&quot; x=&quot;620&quot; y=&quot;250&quot; as=&quot;geometry&quot; /&gt;&#10;        &lt;/mxCell&gt;&#10;        &lt;mxCell id=&quot;app&quot; parent=&quot;1&quot; style=&quot;rounded=1;whiteSpace=wrap;html=1;fillColor=#dae8fc;strokeColor=#6c8ebf;fontColor=#333333;fontSize=14;fontStyle=1;shadow=1;&quot; value=&quot;Application&quot; vertex=&quot;1&quot;&gt;&#10;          &lt;mxGeometry height=&quot;90&quot; width=&quot;200&quot; x=&quot;1140&quot; y=&quot;260&quot; as=&quot;geometry&quot; /&gt;&#10;        &lt;/mxCell&gt;&#10;        &lt;mxCell id=&quot;s1&quot; edge=&quot;1&quot; parent=&quot;1&quot; source=&quot;agent&quot; style=&quot;html=1;labelBackgroundColor=#1C1D1E;endArrow=block;strokeColor=#9673a6;fontColor=#9673a6;fontSize=11;rounded=1;edgeStyle=orthogonalEdgeStyle;exitX=0.3;exitY=0;exitDx=0;exitDy=0;entryX=0.5;entryY=0;entryDx=0;entryDy=0;&quot; target=&quot;vault&quot; value=&quot;&amp;lt;font style=&amp;quot;font-size: 13px; background-color: light-dark(rgb(255, 255, 255), rgb(28, 29, 30));&amp;quot;&amp;gt;① authenticate — AppRole (role_id + secret_id)&amp;lt;/font&amp;gt;&quot;&gt;&#10;          &lt;mxGeometry relative=&quot;1&quot; y=&quot;20&quot; as=&quot;geometry&quot;&gt;&#10;            &lt;mxPoint as=&quot;offset&quot; /&gt;&#10;            &lt;Array as=&quot;points&quot;&gt;&#10;              &lt;mxPoint x=&quot;100&quot; y=&quot;200&quot; /&gt;&#10;              &lt;mxPoint x=&quot;480&quot; y=&quot;200&quot; /&gt;&#10;            &lt;/Array&gt;&#10;          &lt;/mxGeometry&gt;&#10;        &lt;/mxCell&gt;&#10;        &lt;mxCell id=&quot;s2&quot; edge=&quot;1&quot; parent=&quot;1&quot; source=&quot;vault&quot; style=&quot;html=1;labelBackgroundColor=#1C1D1E;endArrow=block;strokeColor=#9673a6;fontColor=#9673a6;fontSize=11;rounded=1;edgeStyle=orthogonalEdgeStyle;exitX=0.5;exitY=1;exitDx=0;exitDy=0;entryX=0.603;entryY=0.996;entryDx=0;entryDy=0;entryPerimeter=0;&quot; target=&quot;agent&quot; value=&quot;&amp;lt;font style=&amp;quot;font-size: 13px; background-color: light-dark(rgb(255, 255, 255), rgb(28, 29, 30));&amp;quot;&amp;gt;② short-lived token issued, cached, auto-renewed&amp;lt;/font&amp;gt;&quot;&gt;&#10;          &lt;mxGeometry relative=&quot;1&quot; x=&quot;0.0547&quot; y=&quot;15&quot; as=&quot;geometry&quot;&gt;&#10;            &lt;mxPoint as=&quot;offset&quot; /&gt;&#10;            &lt;Array as=&quot;points&quot;&gt;&#10;              &lt;mxPoint x=&quot;480&quot; y=&quot;375&quot; /&gt;&#10;              &lt;mxPoint x=&quot;160&quot; y=&quot;375&quot; Line truncated