Accounts and sign-in, and fix the read toggle

epAction's redraw closure called itself when handed a row, so Mark read
recursed until the stack blew; it now swaps that row in place. Opening an
item also marks it read, redrawn where it stands so nothing vanishes from
under the pointer on the Unread tab.

Step A of multi-user: users and sessions tables, Argon2id, a session
cookie, ipx user subcommands, and a trusted proxy header for Cloudflare
Zero Trust -- honoured only from a trusted_proxies address. The shared
token still works and is the admin. A new database starts with
admin/ipodderx.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AdXho5tTkjFLeUXKbEjKBh

Cargo.lock

@@ -109,6 +109,18 @@ dependencies = [
  "rustversion",
 ]
 
+[[package]]
+name = "argon2"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "134c52ddac6d63c576bef8168db10c83c49c26444ecbc68060fef078925a901c"
+dependencies = [
+ "base64ct",
+ "blake2",
+ "cpufeatures",
+ "password-hash",
+]
+
 [[package]]
 name = "arrayvec"
 version = "0.7.8"
@@ -326,6 +338,12 @@ version = "0.23.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ac07cdecf99051d9a5238b80f35af32cdeba5b336e55d957b318b50137e18da5"
 
+[[package]]
+name = "base64ct"
+version = "1.8.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2af50177e190e07a26ab74f8b1efbfe2ef87da2116221318cb1c2e82baf7de06"
+
 [[package]]
 name = "bitflags"
 version = "1.3.2"
@@ -350,6 +368,24 @@ dependencies = [
  "wyz",
 ]
 
+[[package]]
+name = "blake2"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5b5d4d889834ee8ecfc0f8426ad30faf7cdcb10f741a8e6d7224d95325479f6f"
+dependencies = [
+ "digest",
+]
+
+[[package]]
+name = "block-buffer"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2f6c7dbe95a6ed67ad9f18e57daf93a2f034c524b99fd2b76d18fdfeb6660aa"
+dependencies = [
+ "hybrid-array",
+]
+
 [[package]]
 name = "bs58"
 version = "0.5.1"
@@ -508,6 +544,12 @@ dependencies = [
  "cc",
 ]
 
+[[package]]
+name = "cmov"
+version = "0.5.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0c9ea0ac24bc397ab3c98583a3c9ba74fa56b09a4449bbe172b9b1ddb016027a"
+
 [[package]]
 name = "colorchoice"
 version = "1.0.5"
@@ -606,6 +648,15 @@ version = "0.8.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a31eee39dddec8330830986fcd7625edb5a24ec90ea038215273bbc3adb08ac6"
 
+[[package]]
+name = "crypto-common"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ce6e4c961d6cd6c9a86db418387425e8bdeaf05b3c8bc1411e6dca4c252f1453"
+dependencies = [
+ "hybrid-array",
+]
+
 [[package]]
 name = "cssparser"
 version = "0.37.0"
@@ -617,6 +668,15 @@ dependencies = [
  "smallvec",
 ]
 
+[[package]]
+name = "ctutils"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7d5515a3834141de9eafb9717ad39eea8247b5674e6066c404e8c4b365d2a29e"
+dependencies = [
+ "cmov",
+]
+
 [[package]]
 name = "darling"
 version = "0.20.11"
@@ -778,6 +838,17 @@ dependencies = [
  "syn 2.0.119",
 ]
 
+[[package]]
+name = "digest"
+version = "0.11.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f1dd6dbb5841937940781866fa1281a1ff7bd3bf827091440879f9994983d5c2"
+dependencies = [
+ "block-buffer",
+ "crypto-common",
+ "ctutils",
+]
+
 [[package]]
 name = "diligent-date-parser"
 version = "0.1.5"
@@ -1309,6 +1380,15 @@ version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "df3b46402a9d5adb4c86a0cf463f42e19994e3ee891101b1841f30a545cb49a9"
 
+[[package]]
+name = "hybrid-array"
+version = "0.4.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "27f864f10dfb56725ce5ce5472bc52252c8f93a4ab86327122cebf62c5f59a17"
+dependencies = [
+ "typenum",
+]
+
 [[package]]
 name = "hyper"
 version = "1.11.1"
@@ -1558,6 +1638,7 @@ version = "0.1.0"
 dependencies = [
  "ammonia",
  "anyhow",
+ "argon2",
  "atom_syndication",
  "axum",
  "chrono",
@@ -2401,12 +2482,33 @@ dependencies = [
  "windows-link",
 ]
 
+[[package]]
+name = "password-hash"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "aab41826031698d6ffcd9cff78ef56ef998e39dc7e5067cdfebe373842d4723b"
+dependencies = [
+ "getrandom 0.4.3",
+ "phc",
+]
+
 [[package]]
 name = "percent-encoding"
 version = "2.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9b4f627cb1b25917193a259e49bdad08f671f8d9708acfd5fe0a8c1455d87220"
 
+[[package]]
+name = "phc"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "44dc769b75f93afdddd8c7fa12d685292ddeff1e66f7f0f3a234cf1818afe892"
+dependencies = [
+ "base64ct",
+ "ctutils",
+ "getrandom 0.4.3",
+]
+
 [[package]]
 name = "phf"
 version = "0.13.1"