ftp-camera: make the ARW completeness check definitive, not pattern-matched

The first cut of the ARW branch matched exiftool output against
'truncat|corrupt|bad offset|bad format|missing.*end|premature'. Two of
those terms are dangerous: "bad format" and "corrupt" appear for benign
maker-note quirks in perfectly good Sony files. On a network where every
transfer is already struggling, rejecting every ARW would have been its
own outage — and a false "truncated" verdict is worse than useless
because it looks like evidence.

Replaced with a definitive test that runs first. ARW is TIFF: the IFDs
record where each data strip begins (StripOffsets) and how long it is
(StripByteCounts). If any strip is declared to end beyond the actual end
of file, bytes are provably missing. No judgement and no pattern
matching, and it cannot false-positive on a valid file, because a valid
file's strips are all inside it.

The exiftool-wording check remains only as a fallback, narrowed to
unambiguous truncation terms. Anything short of an explicit truncation
report now returns UNVERIFIED (2) rather than TRUNCATED (1), so an
ambiguous validator result never blocks a good RAW — it warns instead.

Tested the overflow arithmetic against strips that fit, strips that run
past EOF, and missing tags; all three classify correctly. The JPEG path
(SOI/EOI) remains the exact one and is unchanged.

Refs: CLAUDE/Plan/00066-ftp-camera-airbnb-wifi-and-hotspot-triage

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Author: LTSCommerce

files/home/.local/bin/ftp-camera

@@ -583,12 +583,46 @@ verify_file_complete() {
             # NOT a completeness signal. That is exactly how fragments got
             # filed under the right date in the first place.
             command -v exiftool > /dev/null || return 2
+
+            # DEFINITIVE test first, where the tags allow it. ARW is TIFF: the
+            # IFDs record where each data strip starts and how long it is. If
+            # any strip is declared to end beyond the actual end of file, bytes
+            # are provably missing. No judgement, no pattern matching — and it
+            # cannot false-positive on a valid file, because a valid file's
+            # strips are all inside it.
+            local sizes
+            if sizes=$(exiftool -s3 -a -FileSize# -StripOffsets -StripByteCounts "$file" 2>&1); then
+                if printf '%s\n' "$sizes" | awk '
+                    NR == 1 { fsize = $1 + 0; next }
+                    # Offsets and byte-counts arrive as parallel space- or
+                    # comma-separated lists; pair them up positionally.
+                    { gsub(/,/, " "); n = split($0, a, " ")
+                      if (off_n == 0) { for (i = 1; i <= n; i++) off[i] = a[i] + 0; off_n = n }
+                      else            { for (i = 1; i <= n; i++) len[i] = a[i] + 0; len_n = n }
+                    }
+                    END {
+                        if (fsize == 0 || off_n == 0 || len_n == 0) exit 1
+                        for (i = 1; i <= off_n && i <= len_n; i++)
+                            if (off[i] + len[i] > fsize) exit 0   # provably short
+                        exit 1
+                    }'; then
+                    return 1
+                fi
+            fi
+
+            # Fallback: exiftool's own structural validation. Deliberately
+            # narrow — only unambiguous truncation wording counts. Broader
+            # terms ("bad format", "corrupt") show up for benign maker-note
+            # quirks in perfectly good Sony files, and rejecting every ARW on
+            # this network would be its own outage. Anything short of an
+            # explicit truncation report is reported as UNVERIFIED (2) rather
+            # than assumed bad.
             local validation
             if ! validation=$(exiftool -validate -warning -error -a -s3 "$file" 2>&1); then
-                return 1
+                return 2
             fi
             if printf '%s' "$validation" \
-                | grep -qiE 'truncat|corrupt|bad offset|bad format|missing.*end|premature'; then
+                | grep -qiE 'truncat|premature|unexpected end|missing .*end of'; then
                 return 1
             fi
             return 0