feat: convenience script to view tables (#2124)

**Executive Summary**

Eyeballing or saving html in a Table element (in the
`metadata.text_as_html` field) takes some manual effort. This script
provides a quick way to do so given an unstructured .json file that
adheres to the usual schema (i.e., that's returned by the Unstructured
API).

**Testing Instructions**

Get some unstructured output that includes a table. E.g. 

[124_PDFsam_Basel III - Finalising post-crisis
reforms.pdf](https://github.com/Unstructured-IO/unstructured/files/13407404/124_PDFsam_Basel.III.-.Finalising.post-crisis.reforms.pdf)

```
./unstructured-get-json.sh --tables --hi-res \
  124_PDFsam_Basel\ III\ -\ Finalising\ post-crisis\ reforms.pdf
````

Then use this the following script to view the structure and content of
the tables: (note that output file was copied to the clipboard from
prior command):

```
./u-tables-inspect.sh \
"<snip>/tmp/unst-outputs/124_PDFsam_Basel III - Finalising post-crisis reforms.pdf-hi-res.json"
```

scripts/user/u-tables-inspect.sh

@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+
+# TODO:
+# * include the page number in output html filename, maybe all tables per page
+#   in one html page.
+
+set -e
+
+USAGE_MESSAGE="Usage: $0 <file>
+
+Requires an unstructured output .json file as the only argument.
+
+Each table in the file is saved as an individual html file and
+opened in Safari (if running on mac), providing a quick and easy
+way to see the structure and content of each Table element.
+"
+
+# Check for the presence of an argument
+if [ "$#" -ne 1 ]; then
+    echo "$USAGE_MESSAGE"
+    exit 1
+fi
+
+# The JSON file to be processed is the first argument
+JSON_FILE="$1"
+
+# Extract the basename without the extension
+BASE_NAME=$(basename "$JSON_FILE" .json)
+
+# Directory where the files will be saved
+TMP_TABLES_OUTPUTS_DIR="$HOME/tmp/tables-out"
+
+# Check if the directory exists, if not create it
+if [ ! -d "$TMP_TABLES_OUTPUTS_DIR" ]; then
+  mkdir -p "$TMP_TABLES_OUTPUTS_DIR"
+fi
+
+# Counter for the table files
+COUNTER=1
+
+# Parsing the JSON and creating HTML files
+jq -c '.[] | select(.type == "Table") | .metadata.text_as_html' "$JSON_FILE" | while read -r HTML_CONTENT; do
+  # Remove leading and trailing quotes from the JSON string
+  HTML_CONTENT=${HTML_CONTENT#\"}
+  HTML_CONTENT=${HTML_CONTENT%\"}
+  # add a border and padding to clearly see cell definition
+  # shellcheck disable=SC2001
+  HTML_CONTENT=$(echo "$HTML_CONTENT" | sed 's/<table>/<table border="1" cellpadding="10">/')
+  # add newlines for readability in the html
+  # shellcheck disable=SC2001
+  HTML_CONTENT=$(echo "$HTML_CONTENT" | sed 's/>\s*</>\n</g')
+
+  # Create filename based on the basename and counter
+  HTML_FILENAME="$TMP_TABLES_OUTPUTS_DIR/${BASE_NAME}-${COUNTER}.html"
+
+  # Increment the counter
+  COUNTER=$((COUNTER + 1))
+
+  # Save the HTML content to a file
+  echo "$HTML_CONTENT" > "$HTML_FILENAME"
+
+  if [ "$(uname)" == "Darwin" ]; then
+    # Open the file in a new browser window
+    open -a "Safari" "$HTML_FILENAME"&
+  else
+    echo "$HTML_FILENAME"
+  fi
+done